Spouse visa extension financial help

[asingh129]

Hi My wife’s spouse visa is coming to end on 24/04
She has been working but went off on maternity leave , since Oct 2021 she has started work for herself which she invoices the company for her hours completed (non-salaried)
- company 1 since Oct 2021 (7 months)
- company 2 since Jan 2022 (4 months)
They have both provided letters of her employment.
she has only been self employed for less than 7 months her tax returns have been completed and it totals £18,800 for the last 7 months from both workplaces. Which categories do we fall under & what evidence would be required?

Thank you in advance