In my experience you have to tell the pilots what speed to fly regardless of the SLP. Like the rest of us when we drive our car they have little regard for speed limits
at times . As for normal speed that depends on the operator sometimes. I have been embarrassed on a number of occassions when pilots bring their speeds right back because the cabin crew are a bit behind. Some operators will not exceed 250kts till above 100, others will hit the gas. This doesnt happen often but please say when you do change your speed from normal operations or because of operator restrictions.
Speed control is a minefield be careful, take full control or dont play with it.