Loss of ST
Whilst I have sympathy for Litebulbs' position, - crudely put that strikers should not be punished for going on strike - we have to examine the law to decide what protection strikers actually have.
The starting point is the contract between an individual (CC) and the employer (BA).
1. Protected from breach.
If a CC withdraws their labour, they are in breach of their contract. The protection from a "protected" dispute is simple - BA can only dismiss them unfairly. - They can still be dismissed, but it will be automatically unfair if the dispute is protected. If the dispute is not protected, BA can dismiss them with no fear of an ET, if they follow a reasonable (not "fair" ) process.
There is a debate to be had about UK law, and whether or not it meets EU requirements, but we are years away from debating this. The EU can only enforce its law directly opposite a State - the UK Government.
The point that really concerns the TUs is the second point.
2. Protected from inciting a breach.
If the dispute is a protected dispute, the TU is protected from civil litigation by the employer when it incites a person to act in breach of their contract. If the dispute is not protected, ANY action by an Official of a TU which might be seen as inciting an individual to breach their contract leaves the TU open for civil litigation for unlimited damages, (and for injunctions).
You'll remember the speed of Unite in rushing out a denial of the window blinds instruction from the junta. You'll also note the Unite rules - only the Exec can authorise ANY action. This is an attempt to protect the TUs assets, which BA could attack if unofficial action takes place in any way authorised by any Official.
So, it all turns on the contract. Was ST in the contract or not? If it was not, then BA can withdraw it whenever/however they decide. If it was in the contract, they can't.
End of. Simples.
The law might be "wrong", but that's how it is.
Faced with bassa's behaviour, (read the court case), BA probably felt they had no option but to do what they did.