That's what we suspect, that it's not practical to test all of the old service packs for a new OS release.
We're migrating from an i520 to an i550, and we'd like to reduce the number of unknowns. Not having to go to a newer JDE service pack would greatly reduce that number. Then again, there may not be a better time to install the new SP.
As for iSeries Access, we always use the version that matches the OS, and stay relatively current with service packs.
Fortunately, we have a decent window to get the new server up and tested, so we may be able to test the idea of not installing the latest and greatest SP.
Thanks for your thoughts.