OC and Sd are very different birds for wait lists. Long beach I believe is more similar to sd, but laguna, forgetaboutit!
My first marina was shelter cove coincidentaly enough. They initially quoted me a year wait list. But if you show up looking nice, polite, and you look like you pay your bills, you will find that wait lists for slips are not chronological, but a screening tool for deadbeats! In took 1.5 months to get a slip and live aboard, but it is a concern to be sure. Drop off enough applications and you will find this not to be the problem it seems on the face. if you are desperate in the short term, move to chula vista, because it’s not a problem.
One other thought, the 40 ft slip will usually take much bigger boats. I was in a 30 ft slip with a boat that measured over 36ft with bow roller and all.