Hi Mark.
Generally if your on grass you pitch sothat caravan & awning are central to the marker peg. On hard standings, pitch so that the awning sits on the hardstanding and doesn't sail over onto the grass.
Most wardens are helpfull folks and will advise their preference.
Last year on our seasonal pitch I was told by the warden to let my awning sail onto the grass as i have a 3Mtr deep awning, 2.5 being usually catered for on pitches as site owners haven't yet modernised pitches to accept wider awnings which are becoming more popular.
Then we had a warden change.
The new chap wanted me to re site the van which I refused to do as there would be a dead patch of grass viewable then.
This year we have returned to the same site and pitched the caravan and awning on the stone, only just though. But the barrels are on the grass.
But they have left the damage to the previous pitch to go to mud. I feel guilty and would buy seed to re-sow grass for them, but after the moaning I had last year another side of me say's why bother.
99.999999% of wardens are extremely helpfull and pleasant people it's just the 0.000001% of "forest grumps" who spoil what is generally a very good relationship.
Having measured the width of my van with the awning up, I know I need 18 feet of hard standing to pitch my van. Now with tape measure in hand I can measure the pitch and determine if the unit will fit. On my current pitch there is a 8 inch discrepancey front to back of the pitch width which doesn't help if you need every inch of stone, does it !
Steve L.