Is it likely that premiums will go up should owners not be prohibited from this type of behaviour in the future?
Interesting thought but insurance premiums tend to go up after actual claims rather than in anticipation of possible problems (beyond what’s already insurable). For instance, I have yet to hear of premiums being raised because there might be electric scooters in a block.
On the other hand, if the scheme doesn’t resolve this, there may be occasion win the future where they have to make a claim – shoddy work leads to a disaster and a new owner of the property refuses to pay, for instance.
My rule of thumb would be if it needs to be done, get it done. Make it clear to the owner why they are in breach of the law and how fighting this in court, without a valid legal defence, could mean that they are up for all costs.