Something wrong was with time.windows.com server. I found that one of my computers set to 1 hour ahead since yesterday.
Just set computer time and restart wallet, soon all start working.
Hmm, I didn't see this on any of my computers. You said max time drift is 3 min, so wouldn't this limit prevent any times 1 hour into the future? Also, the time is UTC so even if time is ahead one hour, UTC time should still be correct regardless of what Windows tells you is the time.
Something buggy, no?
it does seem dangerous that my (correct time) linux daemon/wallet was immediately accepting blocks generated 1 hour into the future. they should have been ignored (at least until the correct time catches up to the block's time.)
It would be interesting to see a postmortem from an expert like vamp. Maybe too nuanced to be meaningful, but curious if it should be thought of as a low probability event that occurred (was it a specific case where majority high-stake pos miners with UTC+1 took over, but chain operation was still robust in the end), or actually a corner case because the fix required outright action from a majority miner (resetting their clock)?
Arguing against the latter point, was the "fix" simply that with enough miners coming online with the correct time it would "clean up" the network adjusted time (baseline
https://en.bitcoin.it/wiki/Block_timestamp)?