Can't exactly remember when LBA introduced SIDs - probably 10 years ago?? Prior to that an individual clearance had to be obtained for most of their flights. MACC issued the clearance. With SIDs, this useful reform ought to have come in long ago.
It's probably only an internal LBA change to procedures since MACC hardly need to be involved. So long as the SID and "Squawk" and frequency are agreed with MACC then there really is no more to it.