Plus the pension they would be getting, add to that interest and then loss of dignity, freedom, health etc etc. 75k is nowhere near.700 sub-postmasters x £75k compensation = £52.5m (or one Erling Haaland). I think the government/treasury can, and should, significantly increase that offer.
I don't know what a sub-postmaster wage is, let's say £40k/yr. Multiply that by 20 years of being fucked around and we're at £800k. Per person.