Thanks to the Nigerian exchange rate (or whatever it is), I just subscribed to the brilliant.org premium, which costed NGN ₦41555 after 20% discount (if you couldn't see this 20% discount, please login to Youtube first, on the same browser session). My bank charged A$40.98 for that.
The lifetime subscription (I could only see it after having paid the yearly) is showing as NGN ₦260000 (~A$250). Let's see how our usage after 1y.
Thank you very much for sharing, this is a fantastic app but usually pricey