is interviewing for an NQ role common as well? My thoughts was that if a firm had openings they would let you know, although there was no guarantee you'd get first choice etc. However I didn't think you would have to send an application and interview (like the TC process all over again!)
It won't be as extensive as a TC process, mainly because the evidence from your time during the TC can be used to support your case as to whether to be offered a NQ role or not.
However, interviewing for NQ roles is fairly normal - not all firms do it, but many do. They are particularly used when they want to be sure you are committed to the team (the last thing they want is for you to take an NQ role and then leave six months later) and/or if they have a choice of trainees to choose from.
Wait until you see what the partner promotion process can look like for many firms - makes securing an NQ role look like child's play!