For some reason, I'm not able to reply to this post: https://www.googlecloudcommunity.com/gc/General-Misc-Q-A/How-to-Disable-TLS-1-0-and-1-1-in-AppEngine...
(/cc @Fabiotbp @mslarkin @chrisgoodman @Codiak @OliRM )
But as of now (March 2025), Google AppEngine is able to block TLS 1.0 and 1.1 without requiring a load balancer, huzzah! https://cloud.google.com/appengine/docs/standard/secure-minimum-tls
This is great news if your site was requiring PCI compliance from an external scanner like SecurityMetrics.