The MPEG2 or MPEG4 issues is a matter of choice by the transmitting company.
In the U.S. DishNetwork uses a great deal of TRUE MPEG4 now, initially it was a fake version for the reason stated above.
The only other NatGeo HD on Canadian Sat is in plain old regular MPEG2 as well.
In Bev's case, unless they only intend it to go to a small handful of users with their latest MPEG4 ready box, then it will be MPEG2 and your current HD gear will be fine.
The current signals are indeed MPEG2 720p HD, so no need to worry.
As speculated, watch and see in February.