BBC Four HD Freeview has moved, cannot re-tune

A couple of BBC HD channels have moved, but in spite of a full re-scan via TV Headend, it's not being picked up. In the pre-defined muxes drop-down box I have tried both my local tansmitter and the generic auto options, it seems that the mux carrying BBC Four HD is not in the list? How do these back-end profiles get updated - is it when updates to TV Headend are posted? Anyone know a way to manually add the mux that the channel has moved to?

Thanks.

Solved. There is a mux at 586MHz from Crystal Palace that my TVHeadend server was not scanning. Added the details manually and some new channels appeared, included the BBC ones that have moved.