I'm afraid we have a fairly major problem with the blockchain atm, and in a way its a lovely example of the problem with PoS coins:

PoS staking was working fine until around the 9th Nov, with blocks being created around the target rate of 1 per minute, but then it got slower and slower until it was approaching 1 per day. This was caused by a combination of not enough SPARK actively staking on the network, and a relatively high minimum PoS difficulty. After waiting to see if the problem would sort itself out it appeared necessary to update the wallet code to address the problem - hence ver1.3 was released early on the 22nd.

Approx. 21:00 on the 22nd a large SPARK wallet (possibly as much as 300k) reconnected to the network - unfortunately before it resynced with the current blockchain it had already started generating its own PoS blocks and because its so much bigger than the rest of the wallets staking for the last two weeks that chain took precedence. Bittrex monitor things like this, I expect some alert went off and that's why we have the post from Richiela at 21:30 about the 55 block rollback.

Two problems now exist:

1) That big wallet wasnt updated to v1.3, so wallets which are updated to v1.3 are rejecting its blocks because they use the wrong difficulty calculation. Not really a major problem because the network weight (amount of staking SPARK) in 1.3 wallets is tiny compared to the 1.2 version, so we could downgrade again without much trouble.

2) The 55 block rollback means that transactions included in the lost blocks no longer exist, so exchange ledgers will no longer balance - deposits and withdrawals will have been cancelled. People have a habit of not resending coins to the exchange when that sort of thing happens, so they end up out of pocket.


The only solution I can think of currently is to enforce a rollback - if I can find a copy of the correct blockchain as close to block 24623 (where it was before that large wallet appeared) I can produce a v1.3.1 which includes checkpoints to enforce that blockchain as the correct one. Edschroedinger has sent me a copy which he thinks is pretty close to that, I havent had a chance to check it yet. Its definitely a hard fork update (again) though, so I can't guarantee that Bittrex or Bter will want to go through all the hassle of sorting it out.