You can use T-Mobile to pay your ETF and then move to AT&T, unless T-Mobile has poor coverage where you are.
Of course Verizon are not affected, existing customers are gladly willing to pad their pockets. I remember reading an article saying Verizon customers pays the highest monthly bills out of all the four major carriers. It's highly unlikely they will have any out of contract discounts considering more subscribers signed up for them last quarter. Verizon market themselves as a premium service, like Apple do.