Is There an Early Booking Discount for 2023 Tours?

I don't know but I would think that if there was one, they would mention it prominently.

But you can contact the tour office directly by phone at 425-771-8303 or by email at rick@ricksteves.com.

I haven't seen one. I think they're just trying to recover from two years of no business.

I booked a 2023 tour when they first posted and there was not an early booking discount.

In our favor, however, deposits used to be non-refundable after 30 days. In 2023, the Tour Conditions indicate the longer period of refundability that became the practice in 2022 is also in effect for 2023:

For tours departing Jan. 1–Dec. 31, 2023
Cancellations, refunds, and credits: Tour deposits are refundable up to 120 days prior to the tour's departure date.

To add to CWsocial’s post:
To tour I signed up for starts 6/4/23. It is refundable until 2/4/23. I’m doing the Berlin, Prague & Vienna tour.

Similar to horsewoofie, my deposit shows in my Tour account as being fully refundable (for any reason, or no reason) until 120 days prior.

And when I've received refunds (2020 and 2022 St Petersburg tours) from RS Europe, they have been prompt.