FLR(M) Renewal and leaving/entering the UK at that time

Hi,

My wife is from the USA and is on the first 2.5 year part of the spousal visa, due to expire on 26th October 2021.

If all goes accordingly with the lockdown easing, we will be visiting the USA on 1st October 2021 until 14th October 2021 for a wedding.

This will leave her with 12 days left on her current visa.

Would we be able to apply early for her FLR(M) in early-mid September? Or are we better off waiting until we return to the UK/would she be able to enter the UK?

Either way, we will be using the Super Priority Service in Croydon for a same day decision as we did for her initial application.

Thanks in advance.

Hi, any advice would be much appreciated on my original query.