If invited them I'm certain BASSA would hold talks with the above. However, for now Bill Francis is the negotiator on behalf of BA.
The first three weeks of negotiations were covered by a radio silence agreement. However, with BA's approval BASSA have released updates on the 24/02, 26/02, 02/03, 06/03 and the 19/03. There is a branch meeting on the 06/04 to inform of the companies and BAs final positions. From there guidance will be recieved from crew on whether to accept or not.