I don’t have experience with being nested or going to a TRB, but for training in general (as a newly certified CPC), some situations notwithstanding, don’t put up with crap from the FAA, your FLM, or your training team. I wasn’t a squeaky wheel, but I modified my days off to match up with my main trainers (wasn’t interested in guest trainers), fired some of my trainers, and asked for new ones by name. When I had two different trainers who worked wildly differently and was told “do what trainer 1 wants with him and do it trainer’s 2 way with him”, I said no. I told the trainers to come to an agreement on how we would do things because I want to do it a set-ish way, and the switching the different styles just doesn’t work for me. I was told several times that, “trainees shouldn’t do that”, but oh well! I bended when I needed to; I wasn’t cocky or gruff about it, but made it very matter-of-fact. Mostly, my FLM didn’t like it, but he had no recourse. Some may see that as “weak”, but as I sit here with my career, I give zero shits. For all the trainees reading this, be respectful, but look out for number 1.