Given the 14 day notice period for strikes, I think it would be reasonable to change the law so that employers aren't obliged to pay staff if a strike is cancelled with less than 7 days' notice.
To make this work, you would of course have to introduce a requirement that those intending to strike would have to register their intention at least 7 days in advance, or else lose the protections afforded to a lawful strike.
It would remain open to employers to agree with unions that staff can come in and be paid. After all, in other industries, things can return to normal very quickly.