I’m not sure I understand. Lip? Reinforce what?
Oh, sorry man. The crutch sits on what appears to be a piece of exposed hull, a "lip", and is pinned to a u-shaped bracket on the transom.
@JimSails stated his concerns about the strength of those connections under sail. It seemed like a valid question.
@Crazy Dave Condon reminds us from time to time how "tender" these water ballast boats can be, so I was suggesting that, should the worst happen, a bright "floaty" might help you, or a diver, find it under water. But I'm sure you're right, the crutch support was designed to hold 1/2 the weight of the mast, while bouncing up and down over potholes and flying around curves on a trailer, for hundreds of miles, every season, for what, 20 years now?
[Edit] The 23.5 and 26 have just a protruding bit of lower hull ("lip") for supporting the mast crutch. The 240 and 260 appear to have an engineered deck for the thing to sit on. Not fair! I'm sticking my IoT 900MHz ISM band telemetry/security dipole antenna at the top of the mast, with my new beer can whirly gig.