Here is a post that supports your position ... it seems that the ACA rules had unintended consequences in your favor ... a sort of loop hole that has not been plugged yet ...
<a rel="nofollow" target="_blank" href="
http://www.hsaedge.com/2016/08/13/your-adult-children-on-your-family-insurance-can-have-their-own-hs...>
