I just saw a follow up to this on Twitter that indicates that
Disneyland will not allow overnight lineups. It is in the same thread posted above. The person that commented stated that he called Disney (1-888-834-9125) and they told him they will not allow overnight lineups and confirmed that they will allow the 6 am entry into the esplanade for those with 8 am reservations through out the reservation period.
I hope this is true! It seems completely strange that overnight lineups would be allowed. It negates the whole reservation system/process.