Thank you Canon USA — they are here!
A Canon EOS R5 and Canon EOS R6 arrived today (retail shipments are currently scheduled to begin July 30th and Sep 1st, respectively). My schedule for the week was just rearranged (in a good way).
Please feel free to ask questions — I can't promise to get to every one, but will attempt that.
It seemed appropriate to create this photo using the Canon EOS R and RF 70-200mm F2.8 L IS USM Lens combination.