Correct calculations for income tax for a small business

Please could you direct me onto the right path. I am in the process of starting a small agricultural business, small here meaning the minimum amount of employed staff as required by SARS to be classified as a small business, but the business has a very high income potential which does not correspond to the financial numbers required to be classified as a small business as stipulated by SARS. The figures exceed the indicated numbers as set forth by SARS. How do I calculate the correct business tax amounts for a small business and still be classified as a small business even if the generated taxable income far exceeds the amounts provided by SARS?

The Small Business is based on the current turnover, not the future anticipated amount.

Thank you very much! This helps

Only a pleasure!