What I would draw your attention to is the definition of “essential infrastructure” in the bill: “a facility or system, whether public or private, that provides or distributes services that are essential”. I think it would be a question of the specific facts and the operational state of that infrastructure.
In theory, something that is still under construction is not actually at that point providing or distributing, which is what we've defined as essential infrastructure here. Obviously, interference with that type of thing may be covered under other offences in the code but may not necessarily fall within the offence of sabotage related to essential infrastructure as in the bill.