Isn't the coding of 'London Terminals' on the magstripe tickets the same for every London Terminal, so the only barrier programming options are probably to retain all or pass all?
Even if that were true, the gateline at London Bridge should still not be swallowing London Terminal tickets with BOJ privs, since that ticket is still valid to at least Waterloo East, Charing Cross, Cannon Street, Blackfriars, City Thameslink (and possibly Victoria?)