Sprint is offering a year of free cell phone service to DirecTV subscribers that switch to its network. The deal — which includes unlimited talk, text, and 2GB of data — is a direct shot across the bows of rival AT&T, which recently acquired the satellite TV provider for $49 billion. AT&T has been offering DirecTV customers up to $500 a line if they switch to its service, but Sprint is hoping to outbid them with its new deal (valid until September 30th).

There are, of course, caveats. DirecTV customers tempted to switch will have to pay a $36 activation fee and buy or lease a new phone, and once their free year is up they'll automatically be moved to a $50 a month plan until they pay off their Sprint device. (DirecTV customers who are already with Sprint can also get in on the deal by adding a new line to their wireless plan.) Anyone who wants to take advantage of the offer will have to upload a copy of a recent DirecTV bill to Sprint's website or drop by a Sprint store with some form of proof.

"DirecTV customers love their TV service, but they shouldn’t have to settle for AT&T wireless," said Sprint's chief marketing officer Kevin Crull in a press statement. A spokesperson for AT&T, Brad Burns, replied: "This ranks right up there with a desperate Hail Mary pass to a petite defensive lineman. With Sprint’s network and the many asterisks on this deal, we’re feeling good about our offers."

Giving away a year's worth of free service is certainly an extreme move, even in 2015's somewhat frenzied wireless market. Still, for consumers there's only one important question: do you save more money with AT&T or Sprint? The answer, unfortunately, depends on exactly what you're looking for in a wireless plan, although CNN Money pegs the upfront value of the deals as $900 from Sprint or $620 from AT&T.

Update August 28th, 12:41PM ET: Updated to add more details about the promotion.