I'll share my experience, although its almost a week old, we just got back from our trip.
I went to HS on 2/18. I took a Lyft from OKW resort and got there around 710-715. No bags, got through the tap stands no problem, but it was a huge crowd. made my way over to the entrance to GE. Also a huge crowd. I was working from my phone, my son is 8, so he doesn't have one. I had my wife work from the room on her phone.
my phone was set with WIFI turned off. signal seemed OK. I closed the app and restarted at 8:00. I never got a red button. not on the front of the app, not when I clicked through on ROTR. tried refreshing, tried closing app and restarting. never went red. couldn't get it. Luckily my wife got me a back up group from the room 91. I have Boom cellular which is a verizon band carrier. my only guess is that with so many people pinging the towers, I was deprioritized and didn't get service.
When they dropped the rope, we followed to MFSR, and it took until 930 to get on. You could barely move around GE afterwards, so crowded. We walked around a bit, but didn't go on any rides. all Toy story rides were 60-120 minutes, same with all other rides included star tours. had lunch then went back to the pool.
after showering we were all going to dinner at disney springs and while we were on the bus our group got called, my son and I jumped off the bus and went to HS. Rode ROTR, then star tours. it is a fantastic ride, totally the best in Disney. The park felt a lot better at 7 than it did at 8AM.
We had a 2nd HS day on 2/22 Saturday. We had a SD FP, we did that, rode alien saucers, saw the little mermaid and Indiana Jones show, then Toy story mania. It was a good day, but still way too many people, fighting over tables for lunch, you almost can't go on any rides you don't have FPs for as almost all have 1-3 hr waits.
The head scratcher I have is, I prepared, I tested the app at home, I was ready to fast finger the boarding group, and we only had 2 people to go on it. I don't understand where I screwed up? Also, frankly I was not prepared to spend 90 minutes waiting for MFSR, or the craziness. I didn't plan my FPs great at HS, we were all supposed to go in the evening and decided not to, so the FPs were planned later. I guess I see others on here getting a lot of attractions done in the morning, either I'm missing something or it just was not possible that day, left disappointed in the AM.