As at the non-updating state snapshotted last night, these SBD balances are backed by a balance of VESTS. These underlying VESTS will be counted and added to the VESTS behind the Steem, and become the new JUICE balance.

The Steem Power will also be counted as of their VESTS value, and converted to Stake, which has the same denomination as JUICE. It's a massive simplification of the Steem currency system, that I think should have been done a long time ago for Steem.

It is in some senses, like a premine, but I know that none of these people premined their stake in Steem, so it was earned, as far as is possible, honestly. They either bought in, or earned it, whether or not the rewards that contributed were assigned by premined votes, does not matter. You have to draw some line. The public offer is now on, and you need only signify your interest to buy in, based on your share already existing in your steem account, as at last night. There will be no ICO, this is going to be the IPO for Calibrae. It is open, in a limited sense, to Steem account holders, but the likely situation is that maybe 100-200 people will sign up, and they will have their VESTS converted to Juice and Stake. From there on, once it goes live, everyone will otherwise be on the same level.