EDIT: Couldn't find it in the JAR explicitly, but here's a quote from Toby Elliott's blog, which is just as good.
Quote from
2) The rule that says you don’t have to remind your opponent about triggered abilities is being extended to Regular REL, bringing the actual rules at all RELs into sync. Of course, the Competitive REL remedy that makes you lose the trigger if you missed it isn’t coming along for the ride. In general, if the controller notices it within a reasonable time frame, and it’s not too disruptive, we’ll resolve the trigger, just like we do now. But, it’s all on the controller to remember, now.
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