That was just speculation and when interviewed, Laine himself busted that theory.
He said that he only uses a new stick for PP to minimize the risk of breaking the stick. Same flex, same lentgh etc.
In the end it would make no sense to have a different stick for PP since it would handle differently.
Laine has a long, 87 flex stick with low kick. The same stick on ES, PP and would be on PK as well.
After the 40. goal (and maybe after other goals too) he might also want to just collect that stick, though this is just pure speculation by me.