What happens?:
For last two weeks me and several other Wikimedians from different parts of Saint Petersburg (different internet providers) regularly have problems with access to Wikimedia projects. It happens daily somewhere in period from 10pm until 2am (not all the time, but every day). Wikimedia Status doesn't report about any problems in that time.
Personally I sometimes see 503 error, sometimes

I sure that it happens with Wikipedia, Commons, for AWB, Chrome and Microsoft Edge, for reading articles and for saving edits. Ends just with time.