Can you all add more info about the check-in / exit immigration lines at TPE in the morning? How long is each step taking typically, and how long before the flight time would you recommend arriving?
Having just done the TPE-SFO flight on 4/9 with the new times, here is my experience (note, I fly this route monthly and am very familiar with TPE):
Arrived TPE at 8AM
Check-in: Quick at the 1K/BF line. Probably about 5 min.
Security: Longest I have ever seen it. With the old flight time it would take 10-15 minutes. This time the line was stretching all the way to the UA ticket counter and had several weaves before you even get past the point where the guard scans your boarding pass. Once you get past that, there were several more weaves before you broke into individual lines for each security lane. Total time - about 35 minutes
Immigration:
All the people from security are funneled straight to immigration. When the security line is long, the immigration line will be just as long. They had all the counters open. Total time - about 20 minutes
The lounges are right after immigration, so I went inside for about 2 minutes to grab some water.
Boarding started at about 9:10AM (boarding pass said 9:00AM).
Overall, I'd say the entire process from check-in to post-immigration took about 30-35 minutes longer than it did when the flight was after 11AM. The EVA lounge has a window that looks down on the check-in hall and the security line. By around 9AM, the line was pretty much gone, which matches my experience from all the previous times I've taken UA872. EVA has their morning rush out of terminal 2 between 8-10AM, so this is most likely why.