This just started in the last 5 minutes for me. The issue being that reports are timing out with esriJobSubmitted.
Looks like it may have already fixed itself (as per below image). Just posting this here in case others run into the same issue today.

EDIT: Looks like this issue is still on-going. It seems that some reports are squeezing through. This is similar to an issue earlier in the year, so if I had to guess, I'd say there is a resourcing issue (e.g., there are an abnormal number of submissions right now).