This isn’t new—the wait times on that US BAEC number have been daunting for many weeks. I am surprised your trial run got through at all. During January I tried calling on more than 15 times to get through, and all but 6 times my call was cut off before I was put in the hold queue, with an announcement that the line was very busy and I should try later. On the 6 times my call did get into the waiting queue, the line was disconnected at the 60-minute mark. Many others were reporting the same experience—-they were cut off after 60 minutes on hold.

So if your test call got through at 35 minutes, count yourself fortunate.

It appears you are trying to add an inbound (return) flight to an existing 2-4-1 booking—-is that correct? Are you aware that you can make the booking online at the T-355 mark when the seats are released, then call later to combine it with the 2-4-1? That is what has been recommended here, and it has worked for me.