doubt it.
Agency staff cost 2x what they are paid and have to be paid the same as they person they cover.
ergo you would see costs double
also they wouldn't know what they where doing as from my exp the jobs that most back office people do in the NHS are madly convoluted because of silly things like IG etc
Only if you assume that (a) every member of staff is currently needed and (b) every task done by the public sector is vital and must be done the way it is now.
I doubt either of these are true...
You're also assuming I'm suggesting hiring temps, I'm not.