I have three connections at home both as a way to increase available bandwidth and also to provide …

I have three connections at home both as a way to increase available bandwidth and also to provide some redundancy since I work from home and my ability to earn income is tied to my internet being up. I have two primary connections that I load balance between, each providing a /56. If either fails, all traffic goes to the other. I have a third connection that is used only as a backup in the event that both the other connections go down, providing a /64. So simple case, I assign an address from each connection out to each device. Except, whoops--the backup ISP only provides a /64 and despite that containing something like 18.5 quintillion addresses (a number so large my spell check is telling me it's not a real word), I can't actually split those up in any meaningful way so I can only allow _one_ subnet to access the internet via that connection. And then I'm pushing responsibility for load balancing between the two primary connections out to each client. You know, to the place with the _least_ useful information for making decisions in this situation. …