Somebody was kind enough (thanks @hzh+17DF6acy!) to share detailed info on the severance package. Pasting that info here to be more easily accessible:
It is 10 days of severance pay per 1 year of services, capped at a maximum of 200 days, which is 10 months pay. You remain on payroll for 60 days, including full benefits, which means you should take care of any medical needs during time period. You all your PTO accurals plus unused floating holidays, but this does not include sick time or sabbatical time. If you do not have that much tenure, each grade provides a minimum amount of lump sum pay. Level 58 should be 4 months of pay if I recall. Don't remember what level 52, 54, and 60 are.