This is good news
For a while, it was looking like Verizon was going to absolutely dominate over AT&T, and be able to corner the market on LTE. Now this, combined with AT&T buying up a ton of SMH from other companies means they will be in similar positions spectrum wise.
I guess someone at Verizon finally realized that the lower and upper blocks can't be used by the same devices... ooops. Although AT&T doesn't currently support Lower A, it would be easy to add to future phones, and plays nice with their Lower B and C deployments.