What is the format of timestamps used to specify which messages to retrieve? Is it time zone dependent?

Timestamps of stored messages are specified as nanosecond-precision Unix Time (UTC). For example, if the following messages are published:

    ["1130"]
    ["PUBLISHED",[1,"Sent","13534398158620385"]] 2012-11-20 11:30:15 -0800
    ["PUBLISHING TO","a"]
    ["1129b"]
    ["PUBLISHED",[1,"Sent","13534398015394044"]] 2012-11-20 11:30:01 -0800
    ["PUBLISHING TO","a"]
    ["1129a"]
    ["PUBLISHED",[1,"Sent","13534397812467596"]] 2012-11-20 11:29:41 -0800
    ["PUBLISHING TO","a"]
    ["1129"]
    ["PUBLISHED",[1,"Sent","13534397502911891"]] 2012-11-20 11:29:10 -0800 
    ["PUBLISHING TO","a"]
    ["1128"]
    ["PUBLISHED",[1,"Sent","13534397410813509"]] 2012-11-20 11:29:01 -0800

To retrieve all messages between 11:29:10 and 11:30:01, submit the RESTful request (subtract 1 on the start and add 1 on the end to force inclusive):

http://pubsub.pubnub.com/v2/history/sub-key/demo/channel/a?start=13534397502911890&end=13534398015394045

And the result would be:

    [[["1129"],["1129a"],["1129b"]],13534397502911891,13534398015394044]