ace and a trump, if declarer is KQxxx x Kxx Kxxx he'll come to 4 spade tricks, 1 heart, 1 diamond, 1 ruff, 2 clubs for 9 tricks, losing 2C 1D 1S in the ending. If we exit HJ, declarer ruffs in hand, DK (club pitch), D ruff, CA CK C ruff, spade off dummy, and I think we get 2S 1C. I can't really come up with a hand for declarer that would bid 2N, but if declarer has the CQ as well then I don't see a beat so whatever