Yeah, prices have been dynamic for a long time. My method for getting better sats is buy the cheapest ticket that can be upgraded. Then, check for upgrade pricing daily. You'll see prices move all over day to day. Buy the upgrade if the price hits your threshold.

I've received a number of upgrades very reasonably priced this way. It also helps that airlines would rather sell the seats for small amounts than give away 'free' loyalty upgrades which keeps seats open.

Side note: but this is also why online privacy matters. If there's little to no data on you, you will appear as a new customer, and you can get really sweet deals.

Use a new browser session, use something like Tor that protects you from fingerprinting, poke around on a VPN, try changing your user agent. Don't log into anything. This is the ideal way to shop.