I think that extending to 65 from 55 will probably delay most people's captain upgrade to at least 3 to 5 years.
If you consider that the company continues expanding and that some people will not extend/make it to 65, then I think 4 years is a good average.
We then take this 4 years and add it to every FO's seniority who joined before 2008. This means that if you are year 3 SFO, you now jump to year 7, and so on. This takes care of everyone who would be dalayed an upgrade.
If you are an SO, then you assume 3 years on SO scale, then the normal progression to FO scales. So SO year 1 would jump to SFO 1.
Does that make sense? Seems perfectly fair to me.
