Spouse visa to ILR - 5 years start

[Riyad]

Hi, I need help please, I'm a British citizen, my wife was granted first 33 months visa in Feb 2015. She was granted a FLM for 31 months ends in July 2020. She is on a 5 year route spouse visa, my question is when I apply for ILR do I have to wait for just 5 years from the first visa issue date to apply ( Feb 2020) or wait until the FLR ( 28 days before it expires) to apply which makes it 5.5 years?

[CR001]

Your spouse's residence starts from the date of ENTRY to the UK. So count 5 years from this date, minus 28 days as they can apply for ILR within 28 days of reaching 5 years residence from date of ENTRY to the UK.