Deejay1:
The limitation for flight with inop window heat (eyebrow windows only) is a restriction to 250kts below 10,000ft.
However, this is from the Boeing MMEL. As to whether
VB has this in their company MEL/DDG is another story.
If you are talking about a #1 or #2 window heat inop, then the same restriction applies, along with a "nil known or forecast icing conditions" limitation. Oh, and the windshield air must work too....