Dear all as a FO with a major British carrier I find myself embarrased to have to ask for help, but I have recently had my understanding of ATC clearances questioned.
When on a STAR into a UK or any other airfield and I'm given a clearance "descend FL150 to be level by XXX"; does this mean at or above, at or below,or indeed at? Furthermore if having started my descent I am then given a clearance "descend FL 90", does the restriction of 150 still apply at XXX? Likewise if I'm taken off the STAR onto a heading do the published restrictions apply.
I hope I am the only one who is uncertain about this but alas I fear not. Thanks for any help with this.
