But reset his DOJ to his 60th birthday.
Nice solution
I have worked for an airline where bidding and leave was based on a rotating seniority list. Every month the top 1/9th of the list was placed in reverse order on the bottom - thus the entire list rotated every 9 months (i.e. on top for xmas this year? Half way down next year & bottom the year after).
It shared the good and bad nicely across the group - and you didn't have to wait 30 years to see a Christmas at home, or a good four day slip.
Promotion, base bids & type changes were date of joining.
... Having said that, I would prefer a rotating list for leave & work bids, and a date-of-joining initial list for promotion/base bids, but with direct entry to initial position (based on hours) for experienced crew (i.e. you can hire a direct entry Captain or high-time FO, and place them into an appropriate position on the list, if you can show they have significantly more experience (say 150%) than the equivalent company employees).