You again have to get the PCC.
I literally have to ask my employer to not to send me to UK before Nov (I had a week trip planned)! I gave personal reasons and my employer was understood as I did not want to take that risk that I entered date of travel after date of my police certificate.
Though I think somewhere on thgis forum I read that it should not be a problem, but I didn't want to take the risk.
Consider this I got UK PCC on 21st May. I went to UK for month in July...I thought why not take the PCC again (given cut off could come low anytime)...I got my UK PCC again in mid of August!
Fortunately or Unfortunately I changed employer and they again sent me to UK for 2 weeks in Sep End and then I got one more UK PCC Dated Oct 25...Though as I mentioned before somewhere I read it was not required! But I do not want to take any risks !