If there are any crewmembers still on strike when the mandate runs out they can be dismissed for gross misconduct - absenting themselves from the workplace with no reason. The protection of the law only lasts for 12 weeks, after this period any striker would be in breach of contract and suffer the same fate as Duncan Holley. As it is a dismissal for a disciplinary reason the normal notice periods would not necessarily apply. I'm not suggesting that BA will do this; it would be an option should the strike continue beyond the 12 week period.
If UNITE wished to conduct further IA after the 12 week period they would need to re-ballot, and give the required notice of IA.
BA also have the option to give 3 months notice of change of contract - as BASSA's barrister admitted in court. So BA could in theory issue everyone with new contracts to be effective in 3 months, again I'm not suggesting they would.
What they cannot do is discriminate against the strikers, so all contracts would have to be re-issued not just the strikers.
UNITE and BASSA have a lot of thinking to do this weekend. Should they elect to conduct a 20 day strike and it is ineffective, what do they do then?