Polymarket V2 started interface switching this week. Discussions in the group are focused on the user layer (USDC.e not returning pUSD / transferring to the wrong chain results in lost funds), but no one is talking about the quieter engineering issues.

I myself, as a trader, am also switching this week. Here's a general SOP for transitioning from V1 to V2, applicable not only to PM:
1. First, just read and explore. Run through all V2 interfaces, confirm that accounts, order books, and market data can all be retrieved. Do not sign any orders.
2. Then, do a dry run. Simulate the order process locally, sign the transactions successfully but do not broadcast them. This step will reveal most incompatibilities between new and old fields.
3. Pick the least important strategy to test. Run it on paper for two days comparing with V1 during the same period. If there are significant differences, go back and investigate.
4. Remove incompatible strategies first. During the switch testing, some strategies are directly removed—if they can run on V1, leave them alone for now.
5. Only then, enable real order placement. After passing all four steps, switch to the real money channel.
The wrap/redeem issues discussed in the group are user pain points. The real challenge is reconciling the state during the coexistence of old and new order books—an account might still have open positions on V1 while placing new orders on V2. This part of the official documentation is not prominent and requires self-discovery.
If you want to run V2 interface comparisons against V1 yourself: