You can resell them if the boat is well used. Silicone will last longer than ten (10) years if they are not aggressively used. There is no recommendation of resealing transom bolts on a time line, just upon checking the silicone and seal condition. If your seeing jackplate travel marks on the transom you are past due. BCB transoms are all fiberglass and have very little compression like urethane foam transoms. Most core transoms are 18 or 24 pound density and they have memory and the bolts loosen, thats not a common BCB issue.
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