As I ve said before, shifting chnls from one TP to another, is done to organize the chnls in such a way that every TP has mix of gud PQ & not-so gud PQ quality chnls on every TP.
So that they are equally distributing chnls amongst all TPs, rather than adding on d same TP everytime.
BAT Update means some changes in TP or s/w is done, and update is send accross to all adtv STBs.