as far as I'm aware , the motor vehicle restrictions for each region are listed in the hunting regs. Tires or tracks , your atv is still an atv and still a motor vehicle.
Last time I checked, the use of a snowmobile for transporting game, transporting hunters and equipment to locations of game, is not banned in BC. Again, each region has it's own motor vehicle restrictions. Use of snowmobiles in some regions is dictated by listed dates and elevations, depending on the region. Some hunts we go with both snowmobile and ATV but only when we get those late draws.
An atv with tracks is not a snowmobile by any stretch