For certain people, myself included, this would actually work out perfectly.  I am paying low electricity cost so I plan on running my S1s until at least October. Would be a waste to get rid of the S1 blades before their usage time is up.  So yeah, lettin them hash out a little more profit for a couple months, then upgrading boards, sounds like a leet strat to me.  Also, Im not just waiting for the board upgrades, pickin up 2 S3s on batch 3.