For ( NR )TDD + FDD Carrier Aggregation we have to align frames.
At the moment we have 3 msec frame offset for TDD, we cannot remove this offset has need to keep synchronised with whole network and also neighbouring networks.
In this case, can we:
(1.) offset FDD by 3 msec
(2.) Can we offset on individual site level rather than whole network and there will be no impact.
In contrast to LTE, NR has flexible TDD patterns so the vendor should be able to provide a shifted pattern without the need to use frame offset
You can go for option 1 but all operators have to do that simultaneously otherwise some may face inter band interference.
Regarding option 2 you ll start facing severe interference on neighboring sites.