Not sure but this short extract from a very lengthy document from Colin Chong a few years ago hints at a significant increase.
Therefore it is clear that the capacity of 52,000 with a fairly low level (4,000) of premium seats requires a significant increase in the price of season tickets across the board including concessions, and a significant increase in walk up ticket prices in order to generate reasonable cash levels over and above the debt service levels and the current revenues generated by Goodison Park.
And that was written when the cost was still estimated to be £500m