its a roster code NOFLY .You get it if you've been involved in a significant incident that needs investigated or a manager has deemed you to be unfit to fly until they've investigated your conduct .
It happens more than you might think .
That is "what the hell a no flying suspension is" it may not even be legal under employment law as you are effectively deemed guilty until innocent , however this is now the easyJet way .
It is worth noting that the head of the flight ops in the CAA is an ex easyjet manager , another senior manager has recently left easyjet to go there and that the flight ops inspectors that are responsible for looking after easyjet also keep their flying current (in many cases) by picking sectors to fly on easyJet aeroplanes .