FWIW regarding advanced pricing, I bought business(/first/whatever you wanna call what they market, but it's a polaris wide body) RT tickets EWR to Hawaii over Christmas last year near schedule-open (early 2022) for arond 3k pp. Monitored the prices all the way to departure. Business class never went lower (bought the last two of the fare bucket) than about 4k. A couple spikes to 6k. Economy, on the other hand, started out at 1200 pp and dropped below 500 close-in. So, maybe dkc715 is onto something that they realized they sold too many cheap fares early on. That said, I recently booked a transcon for like 700 in P for mid-June two weeks ago. Now I don't see anything below $1,000 for EWR-LAX. But then again, SFO-EWR is 2200-3400 mid-June, probably because they feel they have strong pricing power? I think the far-out pricing could be route and seasonally dependent such that cheaper fares can be found if you know when and where to look.

All this said, I was looking at Coachella tickets for the new special flight they are running the second weekend, and yesterday mid-day it was available for $640 RT for 2, and now the flight is nearly sold out for $3,300 for 2. This anecdote is to say that if you have a particularly popular event on need-to-be dates, in my experience booking as soon as possible saves substantial money. Even if it is an interest-free loan to United. To me, this bet of booking early seems worth it if you are willing to make use of the no change fee policy the big 3 now have if the price drops on a carrier you intend to fly again.

My $0.02, YMMV

Edit: same phenomenon as the above Hawaiian anecdote when I went skiing in Aspen, booking 1-stop flights 8 months out. Price never dropped, per my monitoring (shoutout Google Flights, you're an amazing tool),