Nah, they are usually pretty good about granting extensions if you try to be reasonable with them. We had to move a shed and I contacted our town. Basically went back and said it’s the middle of winter and I can’t do it at this time of the season. They came back and gave me a 4 month extension no other questions asked. Of course it was a silly warning in the first place, and I am sure some cities are more anal than others, but for the most part they just want you to be in code rather than tick you off or have you ignore them.