Well depends what outlook you want to take... Technically the odds don't change, the snakes are either het or not, you always have the 1/16 chance if their truly dbl hets. chances of your PH being dbl het are 25%. so you could look at it as having a 1/64 chance.
the 66/50 to your male, well you have a 33% chance of it being truly dbl het, so your chances would be around 1/48
I could come up with other numbers looking at it with different logic, but I think that's what you were looking for. once some snakes prove or don't prove, your odds will get better or go directly to zero.