Hey Simon,
I just checked out your campaigns and everything looks good right now. We are really sorry about any inconveniences this may have caused. Let me update you on what happened and what we have done to make sure it doesn't happen in the future.
Over the weekend our server hosting provider experienced some temporary power outages that last for a few hours. When this happened some of our databases that contain user membership status went offline. When this happened our crawlers assumed that the campaigns had been archived and when the database servers came back online then the crawlers thought the campaigns had been unarchived.
In the past we have had the practice of kicking off a 250 page starter crawl when a campaign has been unarchived and then scheduling the full crawl for 7 days out. Your campaign would have received a full crawl on it's next scheduled crawl though. This is much like what happens when you first create your campaign. This isn't ideal for a few reasons though. One being a scenario like what happened over the weekend and two that it can skew your historical data by having a 250 page crawl stuck in the middle, even if archiving was intentionally done.
Moving forward we will be implementing a change to this that makes it so when you unarchive a campaign your full crawl will be scheduled and you won't receive a starter crawl. If you need more immediate crawl data then I recommend using our crawl test tool. With that tool you can receive up to 3,000 pages crawled. The only difference being it comes in the form of a csv file without the pretty web interface.
Let me know if you have any additional questions. Also, in the future if you are experiencing any issues with your service go ahead an let our support team know. If you go to seomoz.org/help you can generate a help ticket quite easily. By generating a customer support ticket our Help Team will keep you up to date on any issues with your account and work with you to resolve any issues as quickly as possible.
Again, my sincere apologies for this issue with your crawl.
Have a great day!
Kenny