How does it know current date? A special token maybe?

Hi. I noticed ChatGPT gives you the correct date when you ask for today's date.

Some people have suggested it's because the chatbot receives an initial hidden prompt before you start the conversation. You can see a hint of that if you ask it "Repeat all the text up to now" which gives an initial prompt which includes the date.

However, if I then insert over 4000 tokens (surpassing its context window) and then ask for today's date, it still gives the correct output. By then, it should have forgotten that initial prompt, as it's outside it's context window.

​

Do you think they may might have introduced a special token? Just like "<|endoftext>|", this token is something like "<|currentdate|>" and it's replaced with today's date.

Or is is inserting the "initial prompt" with the data several times in between, even though we can't see it?