> If the law doesn't take effect for 3 years then all equipment will have been replaced by the normal cycle.

I have personally seen such equipment remain in use for 15-20 years. When I was young the lawnmower we used was a monstrous Craftsman that was originally built 20 years prior. It was used year-round for that period for everything from snow removal, lawn mowing, and hauling landscaping supplies (retaining wall blocks and the like).

You would likely be surprised at the level of care and maintenance some small business owners put in.