For the client premises equipment it's a hard problem but entirely solvable. Frequency hoping radios have been around a long time. Link bonding has been around a long time. Which satellites will be in view, where, and when is knowable. I think the harder part will be the backhaul... in space.

I'm curious if they'll use beam shaping antennas for CPE. Surely they won't ship antennas with moving parts right? Also I'm curious about the power requirements of the CPE.

Another problem will be security. This is a known problem with satellite uplinks. They basically spray everyone's traffic all over God's green Earth and if you listen in you used to be able to grab lots of data right out of the sky. These days it should all be encrypted, even then some of the encryption was easily cracked.