I actually got a request for PCC on Feb 26, and I asked for clarification on what exactly they asked. Three weeks later, they sent me an email, stating that what they wanted were both a PCC from my country of origin (despite me not having lived there since age of 18 for more than 6 months), and an updated FBI PCC. So I submitted my country's PCC, and just two weeks ago, I sent them my FBI PCC.
I just got my GCMS notes on Friday last week (I ordered for it on March 22, so it took almost a month; some people here got it much faster, not sure why it took a long time for me), and in it, it stated that I passed criminality. Under the criminality section, they included my expired FBI PCC (since the GCMS notes included only information up to March 28, it does not yet have information of the new FBI PCC I just sent two weeks ago). It seems to me that, even though the PCC was already expired by the time I passed my criminality, they still considered it, so you may or may not be asked again for new PCC if you have submitted one that is not more than three months old with application submission.