OP Southwest operates on an algorithm for assigning their Boarding Positions
- A1-15 are only for those with Business Select fares purchased or Upgraded Boarding purchased (which is done at the gate and subject to availability)
- After that is A-list Preferred
- After that is A-list
- After that is Anytime Fares purchased with EBCI in the order in which EBCI was purchased
- After that is Wanna Get Away Fares purchased with EBCI in the order in which EBCI was purchased
- Companion Pass is in there somewhere along with passengers with Anytimes Fares and Wanna Get Away fares without EBCI which is determined by the passenger checking in at 24 hours prior to their flight.
Nothing and I mean nothing guarantees you A Boarding except for option #1. Unfortunately this falls into the category of misunderstanding things. In the future if you fly Southwest and purchase EBCI do so with the understanding that EBCI is not related to Boarding Groups (ABC).