i am not sure if you can process two at once.It is ending in September. I think i will apply it because there is no confirmed processing times and the last thing I want is to be stuck in limbo for no reason.
since you applied for the PR one then the extend pgwp program might just wait in the queue while the PR is processing if the pr is refused then maybe they start working on the pgwp.
I read somewhere if you apply to two different programs they will process the first one that you are applying to.
Need to check the IRCC website to make sure.