Re: Capita has taken extensive steps to recover ... the data
If the statement refers to the original response then it could mean "we couldn't trust the data so we had to delete and restore it". Even if the CNC part of the breach only refers to an outsourced cleaning contract, you don't want someone wandering around HQ with a bogus cleaner's lanyard.
But yes, erased information can be restored and compromised information remains irrevocably compromised.
There is certainly a massive lack of transparency as to what went wrong. Personally my bet would be on a subcontractor brought in to administer systems on the cheap, a la Lapsus v Okta.