I just wanted to hear a really straight and easy answer from an ATC guy or girl! May sound like a really silly question! If I am told to
"descend FL200 level 45 miles before Bovvingdon"
Does this mean:
a) Start descent NOW and there is a level restriction to be met so adjust rate of descent accordingly. But actuall strt descent now to avacate that level. or.......
b) Descend when I am ready to meet that level restriction. Eg maybe 5 mins or so!
Hope this can be answered straight - just ATC guys please as I'm really not interested in a hundred pilots own "opinions"!!
Cheers!