AIUI FCC would not require GSM on 377s for the same reason that SN do.

The Victoria 377 problem is GSM, yes, sure, but it is for postioning
for SDO.

FCC/TL won't be using SDO ... they do not use it anywhere on their
network pre-KO0, there is no need for it at any of the ''underground''
stations. Hence they don't need GSM for this, so the delay etc will
not occur.

I don't know any reason why they will need underground SDO post KO0,
since the relevant stations are already 8car - we are not into +8car
yet and won't be for a long while, nor is FCC/TL putting in SDO. In
any case SPILL is already 12car (and thats the one people seem to be
commenting on) as is City.

There may be another reason for GSM, but not for postioning, and there
may well be GSM/SDO postioning somewhere, but not underground.

The problem therefore should not affect FCC/TL.

--
Nick