HKAOA/DPA?
Wasn't this tried out 3 or 4 years ago?
If my old memory is right, DPA essentially wanted to merge the 2 seniority lists on a straight date of joining basis and the HKAOA response (quite right too) was NO, all on existing seniority lists stayed where they were but pick a date in the future to combine the lists and that might work. DPA said NO to that idea.