Looking on https://www.gov.uk/uk-family-visa it states, "The earliest you can apply is 28 days before your current permission (called ‘leave to remain’) expires. Any time you have left will be added to your new permission to stay, up to a maximum of 28 days."
Does this not mean it would be 4th December 2017 if my wife's visa expires on the 1st January 2018?
What type of visa does she currently have?
If she entered the UK on a 33-month spousal visa, what matters is the date she ENTERED the UK, not the expiry date of the visa, because the visa is valid for 3 months longer than it takes to qualify for FLR(M).
She only has to spend 30 months in the UK on the spousal visa before applying for FLR(M). Then it's another 30 months on the FLR(M), and she can apply for ILR after 60 months in the UK.
So, with a spousal visa:
- Entered the UK on 20th June 2015... this is the start of her 30 months
- Her visa expires on 1st Jan 2018
- She reaches 30 months on 20th December 2017
- She can apply for FLR(M) 28 days before she reaches 30 months in the UK... which may be MORE than 28 days before her visa expires, depending on what date she entered the UK
- This means she can apply for FLR(M) at anytime from 23rd November 2017 to 1st January 2017
But with an FLR(M) visa:
- FLR(M) visa granted on 20th June 2015
- FLR(M) expires on 20th December 2017
- She reaches 30 months on 20th December 2017
- She can apply for FLR(M) 28 days before she reaches 30 months... which is ALSO 28 days before her visa expires
- She can apply for FLR(M) at any time between 23rd November 2017 and 20th December 2017