Yes, Parksavers Magic Your Way tickets can be price-bridged.
What you actually PAY for the discounted ticket does not matter.
Since there is no such thing as a ticket with "Buy 4 days, get 3 days free..."
That would just be a regular 7 day ticket (with a discounted price.)
So, you would subtract the new, at the gate cost of a 7-day ticket from the new, at the gate cost of a PAP,
and you would pay that difference amount (plus tax) for the PAP.
You can use the Parksavers ticket to enter a theme park before upgrading, if you like,
but it is not necessary.