I'm a bit surprised at 'only' 5 being promoted to NL. It sounded like there were quite a few retirements from NL at end of season, plus the three from SG1.
It will be interesting how many get promoted to SG2. I think there's quite a few possible candidates but not sure anyone retired from SG2 at end of season. I'd guess there will be at least one promotion to SG1 but not sure there will be many more than that. Being honest, I think there are some referees on SG2 whose place on the list is perhaps questionable. Some don't seem especially consistent in their performances or seem to have any realistic chance of promotion to SG1, so you do wonder if their continued presence on the list is simply blocking more promising referees from below.