The two cells were never made peers of each other because they do not want multi-band subscribers automatically roaming between cells yet. The cutover to the 700 cell has been slow and deliberate, targeting areas where the T-Band cell has less robust coverage. It'll be a while until the T-Band cell goes away completely.Site 05 is on the air, however it does not show as a peer on Site 6.
I suspect Site 05 days are now numbered.