BE customers have enjoyed the Advance Seat Assignment Offer for purchase since February 18, although it may not have been available in all markets initially.
This topic from March was somewhat related to that.
I wonder if the offer will expand with more options to further increase ancillary revenue. For example, offering BE customers a full-sized carry-on bag with or without Premier Access (including being promoted from BG 5 to BG 2) for purchase while still retaining the restricted nature of the BE ticket so the customer can save a dollar or two vs a regular branded Economy fare with Premier Access.