They are using DSS on B5 here, on one carrier. LTE-only on the other AFAIK.
I kinda hope AT&T doesn't turn DSS on in markets where dropping H+ bumps them from 5x5 for everything else to 10x10. They have 10x10 of B14 and 5x5-10x10 of B12 to throw users on, and with the delays to their C-Band deployment due to waiting for gear their network is effectively LTE-only in many areas despite an increasing proportion of 5G phones. The network was doing just fine without the extra B5 bandwidth, so not a whole lot of reason to basically go backwards when they said they're dropping 3G to expand 5G.
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