Once again thanks for your input, that's very comforting to know.
I wonder if you could help me with what format my sponsorship letter, re my husband should take and also does he need to write one for himself to accompany the form?
You're welcome!
Your husband does not need to write a letter unless there is anything in particular that he needs to explain in more detail than there is room for in the additional information section of the application.
Your sponsor letter should address the requirements and how you meet them.
Mention that you're a UKC ( and thus able to sponsor him), a short paragraph about your relationship and why you are moving back to the UK.
How you are meeting the financial requirement and the proof you are including to evidence that.
Where you plan to live initially and your plans for after that.
That's pretty much it.