The due cause is actually hardship - they will try to convince a judge that because of the financial investment to this point (whatever point that will be when/if it actually goes to court) it would be a financial hardship to force them to move the build. They will probably also try to have that hardship filter to subs who may not be fully compensated for their work to that point - convincing a judge that they would not be able to pay them. Judges don't like to cause people financial hardship when a variance is an option - we've seen that happen in our area over and over. People are way too willing to ignore the rules and cop the attitude that it's easier to ask forgiveness after the fact than permission beforehand and it often works. There is a growing attitude now-a-days that rules are meant for everyone else and we are the exception - a sad reality of modern times.
The longer they continue working, the farther along they get on the project, the less likely you are to see the project halted permanently and it becomes very likely that your neighbors will get what they wanted all along. I would get the other community neighbors together as fast as possible and use whatever means available to stop work.
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NOW THAT'S A BOATHOUSE!!!
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