John Pannell reported the following on Patch-L:
I got a few emails this afternoon that led me to visit my site. Apparently it’s down. I’m not at home so have no idea what’s wrong or when it will be back.  This is not part of the planned maintenance I thought I’d have to do.I have a few aching suspicions about what could be wrong and none of them are very appealing to me.  If I’m right, it is possible that it will not be back up before the Jamboree.
I was able to get in just now although it may have been images in my cache. I did get an error messages or blank screens on some of my searches.
OA Images is the online reference for all OA, good luck to John in getting the site back up. Please subscribe or hit the tip jar to support John’s efforts
It’s back, but I’m less than confident the issues are fixed. In fact I know of at least one significant problem with the site’s server, but I don’t think that will affect users at this time.
I’m keeping my fingers crossed.