One of the issues I have with them going from NL to Oz for the back half of S3 is that by the back half of S3, we’ll all be desperate to catch up on SB, and perhaps even a bit fatigued of always seeing the group that’s gonna be in NL. If they then go to Oz, we’re stuck in the same situation as the first 11, where we have to focus on the group of heroes and what they’re up to, to the detriment of showing SB.
If they go back to SB, we’ll still see those JR6 characters, but the secondary characters, (and Belle, if she doesn’t make it to NL), can be brought back into the mix, so it won’t be JR6 overkill any more. They can reunite with their friends, regroup in a familiar place, and then things can start going wrong again as the setup for heading to Oz in S4.