AT&T confirmed Tuesday that it has ended its incentive program that offered T-Mobile users up to $450 per line to switch carriers. AT&T said when it launched the program that it was a limited-time offer but did not specify how long it would last. 

The program let T-Mobile customers switch to AT&T and trade-in their current smartphone for a promotion card of up to $250. That money could be used toward AT&T products and services and is still being offered by the carrier. However, under the program, T-Mobile customers could also receive an additional $200 credit per line when they transfered their wireless service to AT&T and chose an AT&T Next plan, bought a device at full retail price or activated a device they currently owned. That offer has been discontinued. 

In a tweet Monday night, T-Mobile CEO John Legere cast AT&T's strategy as "#doingitwrong." 

"That was quick! @ATT already revoking the $450 bribe to @TMobile customers? People weren't falling for it, were they #Randall? #doingitwrong," Legere tweeted. 

AT&T rolled out its offer in a move that was viewed by many as a way to preempt T-Mobile's own incentive program, which was announced at the International CES in Las Vegas in January. T-Mobile offered to pay the early termination fees—up to $350 per line—for individuals willing to switch over and trade in their device. With the trade-in and ETF payoff, T-Mobile's offer, which is still running, could go as high as $650 per line (up to five lines per family).

This appears to be only the beginning of the fight between AT&T and T-Mobile. AT&T last weekend rolled out its most aggressively priced plans to date, offering subscribers a 10 GB bucket of data for two lines that starts at $130 per month. AT&T is also currently offering customers a $100 bill credit to add a line to their account.