I was lucky enough to be selected to officiate a 1st round and a semi-final post season District games. I believe the process of selecting officials goes this way. Coaches of the participating schools submit a list of 'Want' and 'Do NOT Want' officials to the Athletic Director. The AD's of the, host schools, gets together with the other AD's, of host schools, and select officials (Hopefully from the list). They select the officials for their final game first, then the semi-final, and so on. This year, School 'A' hosts District games. Official 'A' use to be employed by that school. He was the Varsity Boys Head Coach at one time and he also was the AD for that school. I believe he got selected for all 3 rounds at the school. 95% of the game is who you know, the other 25% is your skill.