I agree; it's just frustrating. For me, the usual CodeForces contest time is 15:35 local time, so on workdays I either work or have classes at the university. The only time I can participate in contests is on the weekends, and there are already very few contests on weekends. :(

Regardless of this, I'll participate in this contest.

I think it's the synchronizing thing, I had this kind of issue before. See this submission with the synchronizing thing giving Idleness limit exceeded and this submission without the synchronizing thing giving WA (it's an another interactive task). Hope it'll help you.