Be sure the shroud shackle is tight and the safety wire is in place. Likewise for the trapeze wire shackle if you have trapeze.
Be sure all fittings are snug around the boat.
Sitting mast up over a long period can work these things loose from the constant motion and or vibration caused by the wind. I would also wrap a line around the mast base and pull then tie off to something to keep the mast rotated to one side. That keeps it from swinging around during the period you leave it.
Be sure the jib cover is used. You could use the main halyard and wrap it around the jib cover (round and round) to take out any looseness that would work free if the wind comes up.
Tie off the rudders to keep them from swinging around.
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