Brilliant news @Summer! As I said in my earlier posts, the tolerance for parents being uncooperative purely out of spite is quite low in the Courts ATM, and I think this decision bodes very well indeed for your case in April. If DH's ex can just come to the party and agree to week about (because after all, that's only 2 extra days a fortnight now) you'll be home and hosed. Even if it goes right to the top of Family Law Court though, I don't think it will cost as much as you might think it will. The higher costs generally come when you have to make repeat appearances due to other issues (mental health, drugs, abuse etc) but generally when both parties are of normal circumstance it all happens in one appearance fairly quickly and painlessly.
I don't blame you for cancelling the hystero either. You have enough on your plate to deal with. Sending you big hugs