It's been a long saga getting to the point where I am comfortable that my new Macbook Pro has FileVault 2 enabled properly on Yosemite.
I ran into the "Encryption paused - connect power adapter" problem several times. Had to do a hard-disk erase and full re-install twice, and spent hours online with Apple support.
Eventually, encryption completed and it told me "A recovery key has been set" ... but never told me what the key was!
Today, I disabled encryption, rebooted, and re-enabled encryption - with the same result.
Eventually, I used
fdesetup changerecovery --personal to create a new recovery key, which I was able to validate with
I now have that key stored in a very safe place (nowhere near my MBP).
But I originally requested, via the GUI, that the key also be stored in iCloud. Now I suspect that the key they have is not the key which will work to decrypt my drive at last resort.
I've spent hours googling, and browsing Apple's support pages, but nowhere can I find out how to update the recovery key stored in my iCloud account.
Any advice greatly appreciated