There is an official guide on financial requirements:
https://assets.publishing.service.gov.u ... .0-ext.pdf
Self-employment income (category F or G):
You must be registered already as self-employed with HMRC and can rely on your latest self-assessment submitted to the HMRC. For example, if you want to apply now, you must provide the latest self-assessment which is for April 2022-23.
Employment less than 6 months with the current employer (Catagory B):
She must satisfy the requirement in two parts
1) Her
current annualised income is above the threshold (£18,600+)
So salary earned divided by the period in which it was earned, then multiplied by 12 must be above (£18,600+)
AND
2) In the last 12 months, she has earned in total, at least the min salary needed (£18,600+)
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