Hello, I am Keith, one of the experts on Just Answer, and pleased to be able to help you with your question.
Any award by the Tax Credit Office (TCO) is only interim and is confirmed at the end of each tax year when all income is known. You must maintain meticulous written records of your students' payments. With that you will be able to complete your annual self assessment tax return and your TCO confirmation also You can then use last year's income as a negotiating tool when applying to the TCO for the following year's credits.
I do hope that I have shown you a way forward in this matter.
I must advise you that you must offer all of it. To do otherwise would be tantamount to fraud.