My GMail account has been disabled.
"Unusual Usage - Account Temporarily Locked Down"
"To keep our systems healthy, Google has temporarily disabled your account. This primarily occurs when we detect unusually high levels of activity on your account. In most cases, it should take one hour to regain access. In rare cases, it can take up to 24 hours for access to be reinstated."
It's been at least 10 hours (Gmail app on my iPhone shows "last updated: 5/22"), and going "welp, you're fucked, wait a day to get your email" is not an acceptable answer. All of the "help" forms have no contact information and no other way to get in touch with someone, so I'm putting out the "hey, Google employees who read HN, tell me who I can talk to about this" bat signal.
I haven't changed my email use patterns at all in months; the message occurs on a browser in incognito mode, I don't use any extensions, etc.
On a more general note, on what planet is "you don't get any email for a day and have no recourse, and we won't tell you why, or let you do anything to fix that" an acceptable action?
UPDATE
At 10:20, my account magically unlocked itself (I did nothing between posting this thread - my iPhone started dinging like crazy and then I could log back in) and is now working again, without anyone waving the magic wand. So, if you run into this, just know you only have to go 10 hours without email, instead of a whole day. I have been using my personal domain for most mail for a while, and this has just prompted me to accelerate that process to at least be able to maintain backup ways to send/receive mail.
I do still hope this thread stays up for a while, primarily so that the workflow around these account lockout messages gets better. It's fine to lock accounts out for security reasons, and I understand that algorithms have problems. That said, there should be more details of what they think triggered the algorithm, and a way to remediate it. If they think it is unauthorized access, try to auth with n+1 factors instead of the n normally required, etc.