COS 08 was simply bringing retirement age into line with the rest of the world. 55 is far too young to retire so some of us took advantage of the opportunity to stay. No regrets from me and when a pax slot (on pax pay) on the 744 offered a chance to never fly freight again in the Classic, that group of pilots would've been mad to refuse. In the transition to COS 08, many just stayed in their pax jobs (and bases) and flew till 65 - then retired. Some underwent a more complicated transition but I don't begrudge those who were allowed to simply stay where they were.
It was a transition period and a few got a very good deal whilst the industry changed to RA 65.