Global LTC Timecode Source

I requested this many moons ago when I were a younger man but am working on a show where this has once again become applicable.

On our setup we have two onstage DP's, Main & Backup, both have an LTC widget attached via USB and both fed with LTC from playback.
All our cue lists are set to look at the LTC widget attached to the main DP, if we loose the main LTC feed and need to switch to the backup LTC feed (or a feed in to one of the consoles, say whilst programming) we have to open up the playback options of every cue list to change the timecode source.
Whilst I appreciate having the choice to have different lists look at different LTC sources it would be nice to also have a "Global" LTC source, one that is allocated its LTC source in the main control panel, that way we can make all our lists look at the "Global LTC" and we only needs to change what source the "Global LTC" is referencing once.

Clever huh!