Sorry I was typing this then I saw your post Fifexile, based on the same information and some assumptions this is what I came up with.
According to a set of Articles I have seen, admittedly from 2019, if the 11th place gets £500,000 payment on relegation and then potentially a payment of £250,000 in the following season if they don’t get promoted. The SPFL must have a £750,000 contingency or insurance policy in case this happens. The 12th place gets £300,000 or 2.43%, which ever is the lesser, of Net Commercial Revenue (NCR) of the relevant season. Then they get £125,000 or 1.01% of NCR, which ever is the lesser, if they don’t get promoted in their first season. If you use 23-24 NCR (24-25 not published yet) and a 6% increase, as they did on the previous year, RC come down with approximately £2,730,505, StJ come with £2,413,110.
We get 1.3% so approximately £610,545, Falkirk go up with just over £1M and Livi with just under£0.9M. So hardly a level playing field and heavily in favour of the SPL teams.
These figures are only estimates, if anyone knows more accurate figures please feel free to correct me.