Judging by the very high number of begging texts for P2s to pick up trips and come and fly on their days off, I don't think those in the pool have too much to worry about right now. That comes with the caveat that if offered SH, take it. Take the first offer you get. Delaying for LH could really come back to bite you in the backside at the moment.
We seem to be desperate on the A320 at LHR the moment. I received five texts asking for volunteers to cover flights at very short notice yesterday, and another five on Friday. They're offering Leave Buy Back in February, which is quite unprecedented. I shudder to think what the summer is going to be like.