How to protect my redundancy and re-hire

Andyb748

Apologies for treading old ground
My wife is made redundant leaving next week having worked her full notice period.
Today she was asked if she would come back for 6 months on a contract basis
Clearly she wants to protect the redundancy payout (a lot less than £30k). She could contract via my limited company in the same service sector.
So, does going back via my company protect her from the long reach of HMRC?
Would a gap between leaving and restarting make that more acceptable?
Would restarting the next day be acceptable if the contract is dated say 6 weeks after leaving and invoicing for work carried out only after that 'gap' despite actually continuing straight after actually leaving?
Hope that makes sense!
Many thanks for your thoughts