On most if not all Comcast systems, the analog and digital channels are simulcast together on the cable. The digital has been there for quite a while already, so it won't affect when the DTA's are activated. The simulcast systems are technically called "ADS" systems.
The DTA has a digital tuner only, as is all recent model full set top boxes.
If the analogs are still there after Comcast said they would be gone, is just one of those deals when they get around to it, their gone.
