The following is a list of many bugs caught on or near leap day, February 29th, 2020. Each link below references the issue with supporting details where available. This list does not include bugs that were already caught and repaired before they could have impact on leap day.
Last updated 2020-05-25 11:32 PM PDT
Verified / Unresolved
Items in this section have been verified, and have not yet been resolved.
- The sports schedule in The Athletic's Android app shows the days of the week off by one. Reports: 1, 2
The issue still remained as of March 9th, 2020. It is uncertain if it was repaired since then or not.
- The command line utility
exa, a replacement for
ls, shows file timestamps from Feb 29th incorrectly as March 1st. The issue was also reported last leap year, but has not yet been repaired.
- The PHP programming language skips over Feb 29th when using
DateTime::createFromFormatwith day of year placed before the year. Reported in 2012, and never fixed. Workaround: Put the year first. (This was in my list from last leap year also.)
- The photo sharing site 500px has problems editing photos taken on Feb 29th. The company acknowledged the issue on March 10th in a support thread, but has not yet reported a fix.
Verified / Fix Pending
Items in this section have been verified, and have a fix ready - pending release.
- The Python package timestring, which is used to parse strings into usable time objects, failed handling dates of February 29th. This led to an issue in HEPData, a site related to high-energy physic data. A fix for timestring is pending. HEPData is working around the problem for now.
Verified / Resolved
Items in this section had an impact on or near February 29th, were verified as actual bugs, and are now reported as resolved.
- Many people reported their cell phones were showing Feb 28th when it was actually Feb 29th, or some variation of showing the wrong date. Most appear to be using Boost phones on the Sprint network, and for at least one, Sprint confirmed the issue and stated they were working on it, while advising customers to set the time and date on their phone manually. Reports: 1, 2, 3, 4, 5, 6, 7, 8
One of these people said things were working better on March 1st, and Sprint has stated the problem has been resolved.
- Users of Shadow, a gaming streaming service, encountered an "L-104 error" when trying to log in from Windows PCs, starting at 4 PM PST on 2/28 (which is midnight UTC on 2/29). The company originally asked their users to work around the bug by disabling time synchronization and set their clocks forward to March 1st. They issued an update about 9½ hours later correcting the problem, and then asked users to turn time synchronization back on. Full discussion on Reddit. (Excellent transparency here, but I don't recommend disabling time sync. That can lead to many other issues.)
- AppDaemon open source home automation software crashed on leap day due to trying to create a date of 3000-02-29. (The year 3000 is not a leap year.) The issue was resolved in version 4.0.2.
- Users of gohenry, a pocket money management app for children and parents, had an issue with scheduled allowances not being paid on Feb 29th. Reports: 1, 2, 3, 4, 5
Go Henry stated the problem has been resolved on March 1st.
- The application Family Tree Analyzer displayed an error message with the "On This Day" functionality, when the day chosen was a leap day. The issue was resolved in version 220.127.116.11.
- Users of TPLink Energy Monitor noticed on Feb 29th that the entire month of February dropped off from daily reported values. One user also noted that the TP-Link Kasa application appeared to have a similar issue, and thus speculated it may be a device-side problem. The problem was reported to be resolved on March 2nd.
- The Python package Faker, used to generate fake data for testing purposes, failed when ran on Feb 29th. The problem has since been fixed.
- The synapse intelligent analysis package for Python had a problem handling the leap day. It has since been fixed.
- The C logging library Stumpless failed on leap day due to a botched conditional check. The problem has since been fixed.
- The open source Animal Shelter Manager software encountered a failure breaking animal records on Feb 29th. The problem has since been fixed.
- The third-party EDDiscovery add-on for the video game Elite Dangerous crashed on Feb 29th. The problem is now resolved.
- Tankathon, a website that provides mock sports draft simulations, reported having a leap day bug on Feb 29th. It was later reported fixed on the same day.
- The networking infrastructure software Krill, which lets organisations run delegated RPKI on their own systems, experienced a bug on Feb 29th related certificate generation. A representative from NLNet Labs reported the issue on March 2nd, and advised all Krill users restart their Krill instances and manually trigger republication. The issue was resolved on March 3rd.
- Players of the video game Dragon Ball Xenoverse 2, published by Bandai Namco Entertainment, encountered a crash on Feb 29th on the first character select screen. The game continued to crash even after leap day had passed. The issue was acknowledged in a support response email from one user. However, multiple inquires to Bandai Namco from other players went unanswered: 1, 2, 3
Some players reported the PC version received an update on March 5th that appears to have fixed the problem. Reports: 1, 2
- Unit tests in the Perl TimeDate module failed on Feb 29th. (This was in my list from last leap year also.) The issue has now been resolved.
- On March 11th, The company behind the subscription management application Bobby App self-reported they were working on fixing a leap year bug. They later released version 3.0.1 to the Apple App Store, with a note in the changelog: "Fixed a bug with dates being off because of a leap year".
- The Python package aioftp, an ftp client/server for asyncio, had a problem related to the leap day with listing files. A fix has been made, and released in version 0.16.0.
Verified / Deferred
Items in this section had an impact on February 29th, but were either resolved through manual workarounds, or resolved themselves on March 1st without any specific fix or resolution reported. One assumes that the responsible party will take appropriate action before the next leap day in 2024, or has already taken such action, but to the best of my knowledge no confirmation of that has yet been provided.
- An automated streetlight system failed to operate correctly for the entire city of Aalborg, Denmark's fourth largest city. It took a few hours of darkness before the city's operations manager could figure out the problem and turn the lights on manually.
- Players of the video game Tropico 6 encountered a crash on the loading screen. The error message shows an Invalid Date error, with a date of 2019-02-29 (2019 is not a leap year). Reports: 1, 2, 3, 4, 5
The game is reported working again, now that we're past leap day.
- The JakartaEE TCK Jenkins Jobs project reported many unit test failures when tests were run on Feb 28th and 29th.
Verified / Uncertain Cause
Items in this section have been verified to have occurred near the leap day, but may or may not have been caused by a leap year bug.
- National Australia Bank’s merchant and business banking facility, NAB Connect, had an outage that started around lunchtime on Feb 28th. It was reported resolved as of 9 PM local time on Feb 29th. It is unclear if this was directly related to a leap day bug or just coincidentally timed.
- A software glitch in the HR software for the Tamil Nadu, India government, delayed salaries for several government employees on Feb 29th. It is unclear if this was directly related to a leap day bug or just coincidentally timed.
- Hotel key cards and elevator access control in stopped working on Feb 29th at various hotels. This was confirmed via a letter from the Crowne Plaza hotel to their guests implicating a nationwide problem with Onity locks. It is unclear if this was directly related to a leap day bug or just coincidentally timed. Reports: 1, 2
- The online gaming service Origin, by Electronic Arts, experienced a massive global outage on Feb 29th. It continued into March 1st. It is unclear if this is directly related to a leap day bug or just coincidentally timed.
Verified / Not a Leap Year Bug
Items in this section have been verified to have occurred near the leap day, but were confirmed to not have been caused by a leap year bug.
The outage was not caused by a failure to code for the leap year. We had instability in a part of our infrastructure that allows our systems to communicate with each other.
A Robinhood engineer also later confirmed that it was not leap year related.
These items surfaced during my search or were brought to my attention by others, however I have not been able to confirm their validity. They may possibly not have happened at all.
- Several people reported that surgical air suction pumps in operating rooms at various hospitals, and other unspecified hospital software, went offline on Feb 29th.
- Some reported the date on their wristwatch skipped over the leap day, including a Timex Expedition watch, and a Casio watch. Another person gave a photo of various Casio watches including several that were working correctly, and an F91W-1 which was not (though that is by design since that model does not keep track of the year, per its documentation.).
- A user of the app for a Brazilian supermarket, Pão de Açúcar, highlighted a possible error with the app on Feb 29th.
- A person reported a possible bug with Patreon
- Some people reported probable leap year bugs with their Amazon purchase experiences. Reports: 1, 2, 3
- Several users of Google Maps have seen wildly incorrect routes for transit navigation on in King County, Washington, USA on Feb 29th. It's unclear if the issue is with Google Maps, or with the underlying data source. Reports: 1, 2
- A person reported that all of the Yealink T56 business desk phones displayed February calendar events for the wrong day.
- One person reported that LinkedIn listed the time they had been with their current employer incorrectly.
- A firearms dealer reported that the E4473 software released by the US Bureau of Alcohol, Tobacco, Firearms and Explosives is having trouble operating correctly today. This software is used by gun dealers to electronically complete Form 4473, registering firearms purchases.
- One person contacted me directly to share a screenshot of the Todoist mobile app, showing "Tomorrow Sat Feb 29", even though it was already Feb 29.
Another person shared a problem with Todoist losing streak data on Feb 29th.
- A person contacted me directly and shared that the French post office system had a nation-wide bug on the 29th that prevented anybody from sending parcels. (Here is a tweet showing long lines at the post office.)
- One person reported on March 1st that their Apple Watch was giving incorrect exercise data for February.
- A user of a Tandem Diabetes insulin pump with Control IQ software shows us a video, and reports incorrect IOB data during the transition between Feb 29th and March 1st.
- A person reported a problem with their Sensi smart thermostat not showing data for Feb 29th.
- A person shows us that their experience with the Chuck E. Cheese Sketch Book (photo booth) printed a date of March 1st when it was actually Feb 29th.
- A person reported a problem with the Turkish government's tax filing system, Defter-Beyan, which allegedly didn't allow February 29th as a valid date. It gave an error message that the declaration period has passed although it hadn't.
- A person reported that the date could not be set to Feb 29th 2020 on a Medisana BU 510 blood pressure monitor.
- A person reported that his transaction dates on PiggyVest, a Nigerian online savings and investing platform, were all displaying Mon Jan 19, 1970 when it was March 1st, 2020. Earlier, on Feb 28th, PiggyVest themselves quipped "February 80th 😫", but it is not clear if they were referring to their platform or not.
- One person reported that cash registers and rewards systems at Qdoba were down on Feb 29th. It's unclear if this was a just single location or if it is related to a leap year bug or just coincidentally timed.
- A person reported that the alarms on his Sonos smart speaker went off on Sunday March 1st, though they were only scheduled for Monday through Friday. It's unclear if this was related to a leap year bug or just coincidentally timed.
- A person reported that his Chase online banking app showed the same credit card payment twice - first on Feb 29th, then duplicated on March 1st.
- Timehop, which made my list from 2016 also, did indeed decide that it's not a bug but a feature! (and with a funny error message graphic!)
- Bantshire University (a parody account, not a real university), let us know that all IT systems are offline due to a complication with a date of March 0th. 😂
- Many developers mentioned that they encountered leap year bugs in their own code. Thanks for sharing! 1, 2, 3, 4, 5, 6, 7, 8
- Not a bug, but something to drink while you fix your bugs now, so they don't blow up next time around in 2024. 😊
You might also be interested in these other articles I've authored on the subject of leap year bugs:
- On the Life Cycle of a Leap Year Bug
- It’s 2020. Is your code ready for leap day?
- List of 2016 Leap Day Bugs
- Leap year bug - Wikipedia
- What are some examples of leap year bugs? - Stack Overflow
Please let me know (in comments below, or send me a DM on Twitter) if you have any corrections or additions. Thanks.