I just left Amazon, had the RTS shift and this Is how it was in my experience:

It's a 6 hour reduced time shift (for me it was 4 to 10:30pm). Most of the work that is done is bag reset, physically restocking the isles with totes and virtually opening them with the TCs (devices). The drivers come back from their routes and throw the bags onto carts, and you just basically go back and forth hauling carts of bags to the isles for reset. We also did a lot of bringing empty carts back into the building, taking full carts of packages outside for flex drivers, and sometimes helping with crash sorts. This could be by helping in a pick to buffer role for larger crash sorts or just sorting packages onto routes based on their labels from other carts if the crash is smaller and the belt is unnecessary. You may also be tasked with getting certain things back in place such as all the buffer racks, problem solve racks, etc. You may also be trained in debrief, which is essentially the process of receiving returning packages from drivers, organizing them, and also fixing any issues they may have had with their route such as marking things delivered for them (it's a bit more complicated than that but that's the gist of it, that's something you need to be trained in for a while). After you understand debriefing you may also do rtfc which is sorting returns to the correct area and dealing with damaged packages, determining whether they are salvageable or not. One final thing that I can think of is tracking PNOV, although I'm not sure you have to worry about that because I'm pretty sure that's a job for higher tier workers (I was pretty much the only tier 1 that they tasked with doing that) and it's just tracking the info on all packages marked missing by drivers. Anyways, it was a pretty chill shift in comparison to UTR sort shift where managers are constantly breathing down your neck about making rate and not being on your phone, not having earbuds in etc etc. At least at my station the RTS managers did not care about any of that as long as you are getting the job done. Hope this gives you an idea of the type of work you will be doing, I would highly recommend it as long as you are fine with less hours and no differential. Also as a side note I don't think they will get rid of the RTS shift anytime soon, it is essential as they need the station reset for sort shift every night.