We just got back (did 3 days June 9-11) did not have express pass but did have early hours since we stayed at a property hotel. That made all the difference. The longest we waited for anything was roughly an hour but the lines do keep moving.
If you want to do hagrids, early hours is pretty much the only way to do it. We waited 20 mins (through a constant moving line). we did it again near closing and waited just under an hour.
We did find that when the express pass line is long, that’s what makes the standby line wait long. Because they will pretty much exhaust the EP line and then let the standby line in after (per an employee) and we noticed this for sure.
For example, hagrids is a constant moving line. There’s no stopping to load (like velocicoaster). So in theory the line should continually be moving. Which is did. Until the EP line formed.
Without EP we rode everything multiple times (hagrids 4 times, velocicoaster like 6 times) without having to wait more
Than an hour. We were prepared for waits though.
By far the longest most annoying wait: pterodactyl flyers. Take my advice…bribe your kid with a toy/treat NOT to do it. It’s definitely not worth any wait.