He rang them just before you posted at 4:50pm and it was busy, and you're surprised by that?
Peak of the peak.
Wait times have increased, but they have a number of ways to contact them.
If he wants an instant answer at peak from a UK rep he's probably gonna have to pay more than he does now.
I switched to Plusnet in October and couldn't be happier. I've had to contact them twice about different queries and was answered within 5-10 mins both times.
I didn't call at peak time.