Really depends on who was let go, since salaries are on such a curve. Back of the envelope guess-timate though, that's 80k per person, and if we use the mean total comp of 191.8k (an SDE II from levels.fyi), that's 80/191.8*12months = ~5months?

Though this is potentially really wrong because it includes stock which isn't really prorated like that, and doesn't include payroll tax and benefits they won't have to pay.