Paint Change
My previous sailboat had VC 17 on it since I sailed on fresh water lake. When I moved the boat to Newburyport and salt water, I changed to ACP 50 anti-fouling paint. You do not have to completely remove old VC Offshore. I sanded it down pretty good,but not even close to completely removing it. Just give it a fairly good sanding, assuming the bottom paint is in pretty good condition to start with. It has worked beautifully for six years now. I touch up the water line every year before launching since that's where the paint really takes a beating. I do add a quick one coat every couple of years to keep it in perfect shape. Good luck. Can't say enough about ACP 50.