Some hours ago we have started to get a lot of behat runs @ CI failing with the scenario:

--name 'Student cannot submit an assignment after the cut-off date'

And, also, have seen some failures with this other scenario:

--name 'Student can submit an assignment after the due date and the submission is marked as late'

Example links:

• https://ci.moodle.org/job/W.03.01%20-%20Behat%20-%20Chrome%20+%20Postgres/966/
• https://ci.moodle.org/job/W311.03.01%20-%20Behat%20-%20Chrome%20+%20Postgres/98/

All branches, browsers and themes affected.

Then I tried locally and, curiously it was passing. So I tried @ CI... and then they were passing also in CI...

As far as there isn't anything landed to integration.git over the last hours looking related at all... I started to suspect that the problem may be time-related, specially with the DST changes that happened 3-4 days ago.

So I tried here, changing the computer's clock and got these results:

• Time set to: Thu Apr 1 23:52:25 CEST 2021 - FAILS!
  (with error: "The 'Add submission' 'button' exists in the current page")

• Time set to: Thu Apr 1 19:53:22 CEST 2021 - PASSES!

• Time set to: Fri Apr 2 14:06:41 CEST 2021 - FAILS
  (with error: "The 'Add submission' 'button' exists in the current page")

• Time set to: Fri Apr 2 19:02:47 CEST 2021 - FAILS
  (with error: ""Assignment is overdue by: 2 days 5 hours" text was not found)

So, really it seems that something weird is happening, not only different times lead to different pass/fail status... but also the error/step where the failures happen is different.

At some point in the time calculations... or maybe in the step transformations... things are becoming out of control, not working as expected.

And this is happening since 26h ago (aprox! Wed March 31 22:00:00 CEST), that's when we got the first failure. Don't know if the failures will also disappear "magically" after some time/days.

Just reporting the dates above because they may be the key to understand the problem.