From what I remember of my time at Waterworld, Senior Managers get 2 free confirmed trips per annum (plus possible extra negotiated contractual additions), these include not just the traveler, but an entire travel party (e.g. several members of the staff members family), and it can be a multi sector trip (with no limits on the number of sectors). These were treated as ID80's (i.e. for offload purposes like revenue tickets, have to accommodate etc.). However as far as I remember these did not come from regular revenue inventory but a specific sub class.

Even though they are "confirmed" tickets there is still a relative prioritisation according to seniority and purpose of travel, so being "bumped" was by no means impossible, they just had to treat you as a revenue passenger if that were to happen.

I do wonder however how much this distorts award availability, since I assume that staff travelers (with appropriate seniority) get much better availability than say a Gold BAEC member trying to redeem miles. If this is the case (as I suspect), then BA has an interesting set of priorities when it comes to rewarding passenger loyalty.