Though there appears to be nothing new, not even an MPEG4 switch, I just looked at
DigitalBitRate and there have been a lot of multiplex/frequency swaps.
These are showing as a massive number of "
Broadcast end channel" highlighted in orangey pink, and "New" labels.
Like I've said already, they've just swapped blocks of channels about, even blocks of HD channels have been moved elsewhere as a whole. And even blocks of SD MPEG2 channels have been moved but
not switched to MPEG4.
It hasn't affected any of my Favourites, as changes on the network often can.
Given they are all moves, but they remain in the same blocks (i.e. their neighbour channels remain the same), and there are no (obvious to me) technical changes like MPEG4 switches going on, the only thing I can think of is this is some sort of preparatory housekeeping, balancing the network in order to make more obvious changes in the future.