AT&T (T 1.12%) said in a blog post yesterday that it's increasing the time customers have to wait to upgrade their subsidized phones from 20 months to 24 months. 

The company said the new policy "aligns device upgrade eligibility with our standard two-year wireless agreement" and will apply to all new customers and existing customers whose contracts end in March 2014 or later.

Two months ago, Verizon Wireless increased its subsidized phone upgrade eligibility time from 20 months to 24 months as well.

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