Pip claim

Hi I have recently been invited to claim pip from dla, I did the initial claim via phone but as yet have not received the pip 1 to check & return. I would have thought they would be sending that quite quick.

Does it take them a while? do they do preliminaries before sending back? do they send pip1 to check& sign at same time as sending pip2? And how long should I leave it before trying to follow it up?

Thanks in advance:)