There's an issue with some users's btcmine accounts for that time period, because I can't access old btcmine stats.
Pool hopping doesn't really work with BTC Mine anyway, so I think people will be happy if you just share the coins for the unpaid shares equally for that site and spend the time on fixing bitcoins.lc instead.
Sounds good to me: just divvy up coins based on your shares' percentage of total shares from btcmine for that period?