Unfortunately removing Huawei and ZTE’s equipment from the current infrastructure might not be as easy or as cheap as you might think. In a report from Globe and Mail (paywall; via MobileSyrup), it has been estimated that it could cost carriers as much as $1 billion to remove Huawei’s equipment from Canadian carriers.
This is because it would involve having to not only remove the antennas that are already in place, but also to seek out alternatives and replacements in the process. So far it seems that BCE and Telus are the most affected, whereas Rogers seems to mostly rely on Ericsson’s equipment (they do use some Huawei tech, but mostly Ericsson).
Of course whether or not the carriers go through with this is unclear, plus there is no ruling by the current government banning the use of Huawei’s tech. However these are some of the possible costs that BCE and Telus might have to bear in the event that they do go through with it, or if Huawei equipment ever gets banned.