Honestly, id be careful with the Prime Day hype for high-end gear. Amazon usually dumps stock of older stuff like the Sony ZV-E10 Mirrorless Vlog Camera rather than giving deep cuts on pro bodies. If you're doing weddings, I would suggest sticking with the Sony a7 IV Full-Frame Mirrorless. Its a safer bet for your $2200 budget than trying to stretch for an R series. The low light is basically what you need for those dark Seattle receptions anyway. Just make sure to check the price history on a tracker before you click buy. Sometimes they mark prices up right before the sale starts to make the discount look bigger. If you dont see at least a few hundred off, waiting for Black Friday might be the move. Also, maybe look into the Sony FE 35mm f/1.8 Large Aperture Prime Lens for those dark receptions, it wont break the bank and stays within your budget.

I have been really happy with the Sony Alpha a7 III Mirrorless Camera for wedding receptions. It works well in low light and I have no complaints. I actually saved a lot by grabbing a refurbished unit during the last sale... it is a reliable way to get full frame and still have cash for a Sony FE 50mm f/1.8 Lens. Honestly, you dont always need the newest thing to get good results.

Quick reply. In my experience, Prime Day is usually a gamble for pro gear. Are you planning to adapt your current lenses or starting fresh? I've tried many setups over the years and you might like the Sony Alpha a7C II Compact Full-Frame for that budget, tho for weddings, the single card slot is a bit sketchy. Data redundancy is key when you cant reshoot a ceremony... dual slots are way safer.