Incidentally, if you do need to get off a beach other than by flying off, I have proven that you can taxi uphill through soft sand - unlike a car you aren't relying upon the wheels to push you and propeller thrust will do it. But, it takes a lot of power and is rather alarming for spectators.
Also (for microlight pilots really) if you are going to have to rig or de-rig, DON'T DO IT ON THE SAND which will get into every available crevise and take months to finally clean out. Find a lawn or car-park that you can taxi to and re-reg there.
I've flown with the inestimable but now sadly retired Tony Wells from Pilling Sands. I think if you get the tides right you'd not struggle to fly circuits in a 747 there, and it has the advantage of being marked on the chart. Stunning place to practice PFLs since you can actually turn the engine off at almost any point in perfect safety (or as perfect as an inability to do a go-around, but the certaintly of a good landing surface gives you).
G