I have a 2016 Cab.Double Agent.
My foil is assembled during the whole season. I ride in salt water. I rarely rinse it after each use.
I take the screws out every six weeks circa. I clean the threads and apply tef-gel on each female thread, reinstall the bolts and clean the excess. I haven't had any seized bolt yet, and they come out pretty easily each time.
Never really bothered on the Double Agent that I passed to the friends around for them to get into foiling (they obviously never bothered either), until the day I decided on short notice to take it away with me on an overseas trip (A 145cm board has some appeal). One M8 wing bolt was getting impossible to remove. Used too much force, head got totally rounded, no way out, no time... The foil appendage just couldn't be packed down and had to stay home! (Blessing in disguise, this forced me to frankenstein the Zeeko foil onto it, and they lived happily together everafter)
Anyway, this stuck bolt eventually did require major surgery, progressively/ carefully drilling all the meat of the bolt out, and re-tapping the threads. A good 3 hours mission, with quality drill bits and taps ... Lesson learnt, a bit of Tef-Gel every now and then saves major hassles!
SS Hoverglide. Salt water. Used generic marine anti-seize. Left it assembled for three months. Was only re-snugging bolts as needed. Then broke everything down for transport. No corrosion issues.
Problem is you can be "lucky" it does not get stuck, or not...
I had an alufoil that even with loads of tefgel, was stuck after 3 weeks only, but luckily it was just possible to get them free by brute force and good tools, but it should not have lasted much longer till it would have been impossible.
I suspect alu and inox even with tefgel, to be a bit like mildew on sails and kites rolled wet - it can happen almost overnight, or hardly never - problem is you dont have a clue if it will happen.
So be very careful, and dissassemble often if you want to be sure (of course only alufoils, does not matter with carbon)
This is what can happen if you don't take it apart often enough. Had a seriously seized both in my mast. Tried a hammer-operated impact driver, then impact/hammer drill but nothing worked. Tried to weld a lever arm on bolt... but failed. In the end had to drill one out and retap. That mast and foil is still going!! I kite in saltwater about half the time. Leave it assembled for weeks at a time (if not months). In addition to several catastrophic bolt seizes I have had a number of close calls. Now I use the silver anti seize with metal in it. AndI try to at least crack the bolts every several weeks.