We switched to premier which supposedly gets us all sorts of extra stuff, but for some bizarre reason will no longer show your daily charge breakdowns.
When you run out of datastore capacity, appengine will start more instances because it sees the lengthening processing times, but that just makes things worse. That you cannot stop.
Our load comes from mobile clients and no humans are involved. If they get an error they try again later. They don't care how long the server side takes to respond.
It is insane that you can't limit the number of instances. appengine would create hundreds at some points, which was very lucrative for Google (our daily fees went from ~$15 to $380 at one point).
Especially since the common wisdom (and from my personal experience as well) is that Google's support is woeful.
-Brian
I see Google developing a bad reputation for customer service (on HN at least. See https://news.ycombinator.com/item?id=6837249 for the most recent example) and some honest recognition of the problem could go a long way to restoring this.
I apologize if you aren't the correct person to direct this to; perhaps you can divert it to the correct channel.