I bound my credit card on August 1st this year and started using API interfaces. I haven’t received the bill from last month yet, and I didn’t see the 4.0 API interface on September 1st.
They will add new users to GPT-4 when they feel like it. Not automatically and instantly based on your billing.
SHHH… don’t tell them nobody got billed yet.
They could have gotten tricky on you and increased the roll-over account allowance higher before charging it to a card.
It is stated on the official website that the payment is 1 US dollar
What they do allow is billing when they want:
We will charge your payment method on an agreed-upon periodic basis, but may reasonably change the date on which the charge is posted.
In the meantime, you can just “upgrade” Bing with prompting.