I'm often dealing with a portion of my traffic being previously converted users. If they've been converted on a pin submit can I send them to a different pin submit offer? Or is that going to cause problems on the pin submit they first converted on?
Nope, shoudn't cause problems at all.
Presumably all PIN submits are independent and non-interacting, unless they are from the same advertiser where the different 'offers' are just front ends to the same back end.
Yeah I was more wondering if it would mess up the long term on the first pin submit. For instance if the converted user only has a certain amount of money on their phone and then they are converted again on another offer the first offer might not get as much money out right?
I don't think so - I believe these kinds of offers won't convert unless the user is on a plan or has the funds there to pay. Otherwise it would be very poor (and preemptive) design on the advertisers part.