All the Stobart sites let you do this, others (such as Tesco) insist we hand in keys & wait in drivers "rest rooms"
Some places insist on Red air line disconnected (which locks trailer brakes) keys handed in & drivers still not allowed in cabs.
It annoys me greatly, I used to sleep for hours whilst backed onto loading bays.
Asda - the ones that don't "side tip" do let you stay in the cab, again no keys....
Why? What on earth do they think is going to happen?