Hi,
Boeing’s automation concept is very simple and less reliable than Airbus. The FMA modes is simple
ARP. Auto throttle Roll mode and Pitch mode in order. In the Boeing , the Pilot flies the aircraft ! So AFDS has to be monitored all the time, religiously.
1.it will not reduce to Flap manv speed. Speed window has to be opened and flap manv has to be manually set.
Although I was told some versions of FMC/AFDS had auto setting feature(not verified ). But surprising even a 737NG has this feature.
Alternatively you can enter the speed on vnav des page in FMC. Without opening the speed window.
2, It won’t reduce the speed unless there is a speed constraint. And speed window should be open for approach.
There is nothing like managed speed here.
Yes you can fly vnav all the way to Loc capture, but the des wind forecast has to be accurate too apart from ISA Devn. At the most you have to add drag by speed brakes to help vnav maintain its profile, that’s the only thing it can’t control.
And Hold modes simply holds the thrust lever in previous thrust setting , aka the AT takes his hands Off , so that the thrust can manually increased or decreased as per requirement Say on Take off roll and descent. Nothing fancy about it.
(And the thrust level will not move automatically till the next mode capture or selection.