@LLC3
I may have misunderstood your question. If you want to do the Roth conversion of the nondeductible funds first, and the rollover back to the 403B second, I believe that will also work as long as it is finished before December 31.
In my mind, it is cleaner to do the rollover back to the 403B first and the Roth conversion after, but I believe that it is not required for you to do it that way.
