If you are Silver or travelling Club, then the Club lounges airside serve most elements of "continental" breakfast until 11:45 hrs approx. So porridge, fruit salad, toast, pastries, cereals yoghurt and what not. So the lounge guides in the Dashboard for more details. The 09:30 hrs watershed is for bacon rolls (and the vegetarian alternative) - they stopped being served at that time. Whereas in Arrivals there is full hot English available until at least noon, sometimes a bit longer.

I don't have any experience of Assistance, but I would jolly well hope they take you up there, it's only a lift ride away from the baggage claim exit which they would have to do for most users. Not sure about onward collection from Arrivals. However I do know they are quite OK about staying airside and transit via Flight Connections, so I suspect that staying airside will be easier. But it shouldn't affect your decision as to where you want to go, I see it as Omniserv's job to merely facilitate that.