Google App Engine traffic splitting doesn't seem to be taking effect
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I'm attempting to use traffic splitting on Google App Engine, but it doesn't seem to be taking effect. I've tried both IP address splitting and cookie splitting, and I've set the traffic to the non-default version to be 99.9% but I still see all traffic going to the default version of my app.

Can anyone suggest what I might be doing wrong here?

A few things that might help:

 - I'm expecting the traffic splitting to take effect immediately. Is there a delay of hours/days before it will take effect?

 - I'm using it on an app that has not yet been migrated to the high-replication datastore. Could this be the problem?
