I didn't realise it was down permanently, ie had ended full stop, just that it's been suspended for a long time now.

I've done the bus transfer twice , the actual travel time on the bus from one terminal to the next is maybe 10 minutes (could well be a bit less), the time is more standing in line witting for the bus to arrive and then to be loaded with passengers and depart. I'm not aware of the frequency between busses, sorry.