Hi. I applied via London embassy. I went down the Muay Thai route too. If it helps:

1. Listed myself as unemployed, selected the lowest income bracket (as investments / crypto returns are in my mind still counted as income),

2. submitted my latest bank statement (valid within 30 days of your application),

3. a comprehensive Muay Thai pack (provider name, copies of their ID, etc.),

4. Copy of recent utility bill

5. A copy of the flights booked - this was actually the only thing the embassy requested as additional documents.

From submission to “additional request” to “pending review” and “approved” took about 10 days /7 working days.

Hope that helps.