Regarding your analysis of the impact of RA60-65: sounds reasonable, if you really believe the expansion will pick-up speed. That would be an optimistic scenario. The reality is that the expansion may remain at the current rate or even slow down with a changing economy, ever increasing competition or whatever unexpected event that may happen in the future (similar to SARS etc). Who can really tell? Any "glitch" in the optimistic scenario and the time to command will increase significantly. Your figure of 4 years delay with RA60 is more likely, and probably 7-8 years with RA65. Under that scenario, "junior" officers will definitely have to work past 55 in order to be able to retire considering the lost revenue arising from a delayed upgrade!
Increasing the retirement age is a significant issue for a large portion of the pilot group and one that could seriously disrupt career progressions. It may be a good deal for the company or senior officers not waiting on an upgrade, but it certainly isn’t good news for the majority. Who would gamble his/her career prospect for a small pay rise or increase in benefits?