Returning to the UK with my non-EU spouse.

[rbsarel]

I am a UK citizen wanting to return to the UK with my US spouse.
I fully understand the spouse rules and MIR. However, I am wondering if my husband can come with me to the UK for six months whilst I work a job that satisfies the MIR?
What are the chances of him getting in the country? We will leave our US jobs open and have return flights, but will the IO give him six months? or are they more likely to give him a shorter time.
He has had two three-month trips to the UK in 2013 and 2014 and one 6 month visit on a marriage visitor visa in 2015.
Thanks for any help.

[Casa]

As a non-visa national your husband will need to carry with him the same evidence of ties to his home country that he would submit in a visitor visa application in order to convince the IO at the Port of Entry that he will return to US without overstaying.

How will he justify 6 months leave from his job in the US