Quick reply received from Mr Affiliate. Looks like you'll need to chase them if not already received:
"August 2023 payments were sent out on 25th September 2023. If you have not received your funds, kindly provide us with your account ID or username so that we will investigate."
To update: there is no update. I've not received payment or a reply but I did notice today that August's revenue (with September's) is showing as 'pending' (ie. not paid) in the backend. Stay tuned for exciting updates.
"The query has been raised with finance for further investigation. Meanwhile, the payment is open and will be included in the next payment run. We apologise for any inconvenience caused."
Not the most ideal but I'm not going to go nuclear over a few hundred. Will be interesting (to me) to see if payment does arrive correctly later this month.
Not yet (I'll post in here when it arrives) but a couple of days ago, my 'outstanding balance' was increased to include both August & September revenue. So, I'm hoping the next step is payment.