Just three days after the official announcement Canon added the new R3 camera and lenses to the list of delayed products because of high demand (this is now standard procedure for pretty much every new product):
Apology and guidance regarding product supply status
Updated: September 16, 2021
Publication date: July 10, 2020We have received more orders than expected for each of the following products, and it will take some time before delivery.
We thank you for your many orders and apologize for any inconvenience caused to our customers. Thank you kindly look forward for your understanding.
[Applicable products]
The Canon R3 and new lenses are now available for pre-order:
Via CanonRumors