I got "in line" for a callback at 8:30 Saturday morning.
At 3:20 on Sunday morning (so nearly 19 hours later) my phone finally rang. The worst part is that once I got my call, I then waited almost ANOTHER full hour listening to hold music before I finally got someone on the phone to sort out my problem.
I hadn't thought of calling an overseas number. I hope I do not find myself in a situation like this again anytime soon, but I will certainly give that a try next time.