If you purchased your VariEze wing fitting from Ken Brock Manufacturing, you will notice that the AN-4 bolts have a longer than standard thread. These threads as they are on any AN bolt are not cut threads, they are rolled threads. If you see any evidence of the threads having been cut with a threading die, discard them and install new bolts. Look for any corrosion on these bolts. Any corrosion should be carefully cleaned off and the bolts should be greased before re-installing them.
Excessive corrosion is cause to discard the bolts.
If you did not personally install the bolts, you may have to assume that they might have been over-torqued. Any suspicion of over-torquing is cause to discard these bolts. If your wing attach fittings were not manufactured by Ken Brock Mfg., you will need to carefully inspect the tapered plugs for perfect fit in the tapered holes. If in doubt, you may have to carefully lap each plug into its tapered hole, checking for perfect fit with engineering blue. Check to be certain that the tapered plugs do not go too deeply into the tapered holes.