DBS checks take a avariable amount of time, depending on the level of check and the amount going through the process, doctors and nurses, especially for ITU need enhanced checks against both vulnerable adults and children.
Crapita used to run CRB checks, and lost the contract, so they have form at knacking this up.
All the big outsourcers are as bad as each other, but the advantage they have is a big recruitment organisation and a rapidly flexible workforce, that can ramp this up quickly, Ideally, this should have been run in-house, but the volume and fragmentation of recruitment and need, make the added capacity dificult to manage, so an outsourcer is the only option.
Knowing Capita, they have undercut everyone, but it will take longer and cost more in the long run.