On the assumption you are inbound on a STAR routeing (as you will be unless you have negotiated a clearance to join direct outside the Airways CAS structure), what will be the terminal fix you have in front of you on your chart and presumably in the FMS as its your filed route, ?
If I was going somewhere unfamiliar then the FMS would be setup exactly as the STAR. For EDI the primary plan will be setup with NEW-OTBUN-HAVEN-centerfix since 99.9999% of the time we are on vectors shortly after NEW. The FMS does have a secondary plan page where the full star will be stored and if necessary we can go to it with a couple of button pushes.
250Kts or less 30 before NEW is pretty unbelievable
It has only happened once and it was not due to wx or pan/mayday etc but as you say, at or just after NEW is becoming more common.
back to holding speed by the entry fix to keep you in the holding area, designed for 210Kts I think
The hold is 210kts for us but if the entry from TARTN to TWEED is flown at 210 then it makes for a very strange entry as the radius of turn is not big enough. 250kts works fine and the slow to 210 wings level to tweed. I'm sure that the aerads used to have a note to this effect but we no longer use them.