AT&T is dangling a tempting deal in front of consumers in what looks like a preemptive strike against upstart rival T-Mobile.

The company has announced that it's giving current T-Mobile subscribers a credit of up to $450 per line for switching to AT&T and trading in their old smartphone — a $250 base credit, plus $200 per line. That's $100 more than T-Mobile is reportedly going to offer switchers to its own network.

AT&T's announcement also beats T-Mobile on timing. Although rumors about T-Mobile's potential switch plan leaked as early as Dec. 20, the nation's fourth-largest carrier hasn't publicly confirmed the plan. Experts expect it to be unveiled next week at the Consumer Electronics Show in Las Vegas.

This gives AT&T a few days' head start on outmaneuvering the company it so recently sought to buy. The renewed competition ultimately serves the rest of us. T-Mobile floated a new idea — paying for your early termination fees — and AT&T responded. This is how business is supposed to work. A spokesperson for T-Mobile did not immediately respond to a request for comment.