Google stating problems occurred as a result of "routine maintenance"
'During routine maintenance [from 1pm to midnight PST yesterday], a number of users were signed-out from their Google accounts. This may have resulted in you being signed out of your account or seeing a notification about “A change in your Google account” or “Account Action Required.”
We hear your concerns that this appeared to potentially be phishing or another type of security issue. We can assure you that the security of your account was never in danger as a result of this issue.'
So, cock-up rather than conspiracy?