I was able to refund my April ticket with tripster and will be able to do it again in late June for my July 6 plans if needed. Connected to MDE in both cases. Not sure if the policy is different because of current events (hadn’t used tripster before) but it doesn’t seem to be.
Another liner recently did some digging on undercover tourist policy Can fixed date tickets be returned to Undercover Tourist if they've been linked to MDE for Fastpass?