The IRS website itself says that the "Where's My Refund" tool updates once every 24hrs, usually overnight. Link below.
https://www.irs.gov/about-irs/the-2023-tax-season-has-begun-irs-offers-tips-to-accurately-file-your-....
And then there's this video from TurboTax/Intuit. https://turbotax.intuit.com/tax-tips/tax-refund/video-what-days-of-the-week-does-the-irs-deposit-tax...
If you watch the video or read the transcript,
I believe it says the IRS updates your refund status once per week on Wednesdays. And there are 2 days during the week where the send refunds. One day is for direct deposits and the other day is for mailing paper checks.
And if you think that's rather confusing, when you try to Google the question (or anything similar) many pages will say the IRS updates once a day during the week - between 12 A.M. and 6 A.M. in the morning.
I would think the first answer I gave is most reliable, being that it's directly from the IRS website.
