You can always move your bitcoin without Block using the two keys you hold, even if Block servers are unreachable. And if you can’t get the Bitkey app from the app stores anymore, you can move your bitcoin using Bitkey’s Emergency Access Kit (https://support.bitkey.world/hc/en-us/articles/24395170222868-What-is-an-Emergency-Access-Kit-and-how-does-it-work) using your hardware and cloud backup. Are there other scenarios you’re looking to use seed phrases for?