Shoey the continuance to age 65, as part of a multi-crew cockpit, is dependent on the other member being under 60 yrs of age. There are other restrictions as well, which have been discussed on PPRuNe previously. I believe the restriction has just been lifted in the USA and requires the over-60 to undergo 6-monthly medicals and line-checks. We all age at different rates - I wake up every morning feeling like a 25 year-old, but my wife won't let her in!