Yes, if your seniority date is in June, you'll receive a double raise. If your seniority date is after August 1, but the contract has not been ratified, you'll also receive a double raise. If your seniority date is after August 1, but the contract is ratified before August 1, you'll receive only the 70c (or whatever else it may be). Thereafter, you'll follow the same wage schedule as everybody else. (Do you have a June seniority date? In my facility, there are no June seniority dates -- everybody hired during the summer is considered seasonal and receives a September seniority date.)
BTW, while I'm hoping you receive the catch-up raise -- and I would welcome one, too -- it appears at this point there may not be a catch-up raise, and just a bump to the starting pay.
This is incorrect; see page 65 of your contract. Status quo, the "four-year progression" is simply a two-tier wage system designed to screw employees hired after a contract is implemented, and ends when a new contract is signed.