I probably meant RA; but yes, when you chop over you lose SDA and convert over to the generic hazard pay. I'm think it was a bit of an increase, but it's something because of how the SDA regulations are written (but also why the SDA backpay came through because it shouldn't have ever been stopped while in DWPs). Unfortunately the tax free only started for the last few weeks of the ROTO, but was still a nice post Xmas gift.
Honestly though the ROTO on the ship was the easiest sailing I've ever done, even though we were sitting off Syria, in the Black Sea and otherwise in interesting parts of the world within weapons range of sketchy people. We sailed in pretty good shape, with a full crew, got proper material support while away, and got things like mobile repair parties for major issues, all without some jackass cramming the flex with everything they could think of so actually got to fix broken things and do only our primary job. The TRP, class shock trial and 'local sailing', were much more actual work, which was on top of basic stuff like fresh water, hot water, toilets etc not working reliably.
If we were to actually sail like that normally I think that would change a lot of the retention issues, at least on the MSE side. Crazy that wanting time and people so that you aren't 1 failure away from disaster on a warship doing peacetime sailing is an aspirational goal. I don't see that happening though without cutting ships to crew the other ones, making 6 week SWPs actually 6 weeks long, and doing radical things like considering delaying sailing if that means you can fix major issues by delaying departure for a day or 2.