There will be a scheduled maintenance on Google App Engine, where we run BTBuckets profiling engine, on April 28th and May 5th, both from 1 to 2 pm Pacific Time.
Any changes made on your buckets and targets will not be available during the maintenance, however, users will still be clustered and the targets will run, without any limitations. We will save and queue changes made to the BTBuckets accounts and will synchronize them once the maintenance is over. If you have any questions regarding this, please feel free to contact us
If you are also an App Engine developer, you might want to check the blog post, about how to gracefully degrade your app during the maintenance, here