scaredy, of course it depends on what has sold around you for the last six months. Perhaps comparable sold comps have either been selling for a higher price in the last six months, or, if you’re in a “custom area” (wine country?), more expensive properties have recently sold than what sold six months ago.
Compare your three recent sold comps on this recent appraisal to the three sold comps on the appraisal that was done six months ago and you will have your answer :=]