They deployed an update yesterday to no longer accept the older ARI draft 01. It sounds like win-acme needs to be updated. (Though ideally it should have dealt more gracefully with not being able to get the ARI info; a client should be able to make its own decision on whether it's close enough to renewal if it has a failure getting the data.)
Are your certificates actually near expiration, or is this just a message in the logs that it can't tell on its own which certificates are near expiration?
It looks like win-acme is still implementing draft-ietf-acme-ari-01, which they said was going away, and Let's Encrypt's server actually failing on the old requests was released to production yesterday (as far as I can tell, I haven't seen an actual announcement about that).
(I'm going to update the title of this thread to try to direct people here, since I'm guessing other people may run into the same problem.)
Just reading through their changelog from when win-acme added ARI, it says that checking "can be disabled using the RenewalDisableServerSchedule setting". Looks like that's in a settings.json file. Might be a workaround for the meantime. (I haven't used win-acme myself, but I have experience poking around documentation. )
Thanks for the confirmation. I was pretty sure from looking through the unofficial version tracker and Boulder's Github that it went out around noon-ish US Eastern Time yesterday, but it seemed a bit odd to me that the official announcement just said "early April" and never specifically said when clients that hadn't updated would start breaking.
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