PPL to CPL (advice wanted)
Bob.
Having a CIR is definitely not crucial. So I don't know what bunnies you been talking to.
But having a CIR when you get your first job thrashing around the top end would certainly be helpful. Especially if you do something silly, like end up in cloud in the wet season. Having a CIR could save your life.
Why not get it early on? It will certainly help with the hour situation when looking for your first job.