Had a brilliant experience last summer on a QR operated BA flight EDI-LHR. Pre departure drink and menus (for brekkie) delivered in order of boarding but orders taken (after doors closed) in order of status it appeared by the zig zagging across the cabin. Me being a lowly Rust at the time! The fixed cabin size obviously helped but status passengers (even Bronze) were asked how they would like to be addressed, seemed non status got sir or madam.