Actually airtel plays pretty clever, they have different versions of packages according to the months they were revised in. So say i have July 2014 Mega 19 HD pack then i will get new SD channels added in new version of Mega Pack HD in my old version pack but i won't get the New HD channels added in Mega HD October 21 HD pack, for that i have to upgrade and pay according to new charges of the latest version . If u do not upgrade then u will stay on the sam pack till 6 months completion from the day u activated that pack.
Earlier doesn't used to give even any new SD channels added in older versions of the packages but now they have altered that policy but for HD channels , the earlier policy remains still.
In Videocon d2h, if New SD and HD channels then u will get the new channels according to whichever package u have opted for and in which package Videocon has allotted those channels plus u will get 6 months price protection from that date and extra amount of PP will get credited into ur account if there has been price increase
In Tata Sky too channels will get added in ur package and if there is price increase then till 6 months u will be carged the old price itself
