Actual tax point vs. basic tax point

Dear my respected tutor,

“2 The Tax Point
(a) It is very important to correctly identify the time of supply or tax point, as this determines when output VAT will be due.
(b) The VAT rules that determine the tax point in respect of a supply of goods are as follows:
– The basic tax point is the date goods are made available to the customer or service completed.
– If an invoice is issued or payment received before the basic tax point, then this becomes the actual tax point.
– If an invoice is issued within 14 days of the basic tax point, the invoice date will usually become the actual tax point. ”

Above is a copy from the lecture note. I am wondering what the actual tax point would be if the payment is actually received after basic tax point date but before invoice date (where invoice is issued within 14 days from basic tax point)

For example: basic tax point: 10 September
payment actually received: 15 September
invoice issued: 20 September
In this case, what is the actual tax point?