I've seen several websites claiming there were payments going out today here are a few of them.
https://savemytaxes.org/irs-ctc-monthly-payments-tax/
https://www.homeatlasths.org/child-tax-credit-payments-2024/#:~:text=Starting%20from%20July%2015%2C%....
https://baltimoreoutloud.com/wp/irs-child-tax-credit-in-2024-ctc-eligibility-and-amount-details/#:~:....
These were the main ones I found. And honestly if you type in a Google search (2024 CTC payments) several articles come up claiming that payments were being sent out today.
