Well, now that he is 268 gms. i would want to know if that is the same hide he had when he was 92 gms? The 10-15% rule is a good one, so is the rule of feeding a prey item that is close to or slightly larger than the widest circumference of the animals mid body. A slight bulge is what you want to see without stuffing or giving multiple items. Maybe he is ready for a larger hide although its ok for him to roam around after feeding. Signs of underfeeding will vary based on the extent but a hungry snake will initially continue to move around pretty much continuously, repeated tongue flicking and overall more active. Stay in peace and not pieces. A.C.