50/50 redirect not working properly
Our redirect experiment has been running for 65 days now, but in the last week, something weird started to happen.
We're redirecting all new traffic 50/50: 50% to URL A and 50% to URL B. Everything worked great until the beginning of the July, the traffic was split evenly, but from the start of this month, more than 10% of the new traffic is redirected to URL A.
What could be the cause? Is it time to stop the experiment and run a new one? Should we switch to server-side experiments?