BI

1. Birmingham UK. (HCO PL 2 Mar 59, HCO Cable and Dispatch Designation System) 2. Board of Issues. (BPL 23 Dec 66R) 3. bye = goodbye. (BPL 5 Nov 72RA-1) 4. the Saint Hill Special Briefing Course student in a Unit is designated for the classes being studied for, as BI = Class I Unit B. (HCO PL 14 Oct 65, Course Pattern)