How to calculate ‘genuine and effective’ earnings

Hi Valerie,
I am a British citizen and I started my business here on the 12th September 2020.  I have a question about the Brexit requirements for micro enterprises.
I will be applying for my WARP/carte de sejour and I’m aware that my business must be deemed ‘genuine and effective’.  In deciding this, do they look at the average earnings over a period of months or do you have to meet the requirements strictly each month?
I was advised that ‘genuine and effective’ means having the same minimum income as RSA/inactif (so 564,78 euros in my case) - I think this is contestable as the cases before the ECtHR seem to say that you only need to work between 12-14 hours, but of course I don’t want to have to get into that so I want to satisfy the 564,78 euros requirement to be on the safe side.
I didn’t receive payment for the majority of my work in November into my bank account until early December.  I received a small payment from another client into my bank account in November, but not enough for the 564,78 euros figure.  Yet when I average my earnings from October, November and December, these 3 months reach the figure when averaged out per month.  So I’m hoping the figures can be averaged out and not strictly per month.  Please let me know if the case.
On that note, do you know how many months of earnings you have to show for the WARP/carte de sejour application?  Would it be possible to only submit the December earnings or would they need a longer time period to show that the work is ‘genuine and effective’?
Thanks