This is a old leak.
More interesting is I've yet to read a write up of where the leak came from, the question asked when it came out -
https://www.schneier.com/blog/archives/2009/11/leaked_911_te...
Is it reasonable (not is it possible) a private citizen was at the time recording all pager traffic?
Can you read them passively and is it location based and does this data fit with that?
If it's not totally passive, would the network notice you vacuuming them all up?