Actually, it's not slush finding a block, it's when the next block slush has found hits 100 confirms and can payout.
Ukyo, can you confirm the following? A user is only rewarded, when they contribute to find a block and this block receives at least 100 confirmations to be credited, as shown here:
http://mining.bitcoin.cz/stats/?Right now the newest completely confirmed block is #20087 which was mined on 2013-09-18 at 09:42:58 AM UTC. This is more than 15-16 hours ago.
This doesn't match with the fact that they are not yet mining or started to mine not so long ago:
I am going to let the mining speak for itself when the pool merge is complete. I would like to note however that even with 5+ TH solo-mining it can easily take 2+ days to find a block due to variance, hence the move to pool-mining.
EDIT: Ytterbium might have a point:If the reward is actually for that block, then that reward MUST have come from a miner who knew about LC's address before it was publicly posted.
So "someone" would have to know about their address for at least 15-16 hours?