Complexities with starting an upgrade beginning with PY


We are in the midst of planning for an upgrade from 9.1 to 9.2. We are running on iSeries and currently have 3 LPARS. E1PROD, which has the production path code, E1DEV, which has DV and PY and E1CRP, which is a newly created empty LPAR. This LPAR was created so we could have each of the three environments running on different servers, so they can be restarted independently.

Since we have an empty LPAR available to us, our plan was to copy down from PD910 into E1CRP and perform the upgrade there and create PY920. After this we would then wipe E1DEV and create dv920 in e1DEV and so on.

My question is - Are there any technical challenges to doing this? Does DV have to be upgraded first? Are there any 'gotchas' to watch out for.

Any comment is highly appreciated.