New job and working out 6 months of payslips

Hi everyone hope you are all well.

I’m asking this question on behalf of a family member who is applying for ILR next year. His FLR BRP runs out at the end of Feb 2024.

He started a new job on 19th June and received a pay slip on 2 July 2023 for the period of 19th-30th June which is less than the £1550 requirement.

He gets paid on the 24th of every month so was hoping to use the following months:

July 24 2023
August 24 2023
September 24 2023
October 24 2023
November 24 2023
December 24 2023

Can he apply using these payslips anytime after December 24th? I’m thinking he needs to apply in the new year to make it six calendar months from July- Jan? Also does he need to include a note from his employer explaining the July 2nd payment as it will show up on his bank statement?

Thanks in advance for any advice. Despite having visa applications on my brain for the last 7 years it’s amazing how quickly I’ve forgotten the basics!