All responses from the subscribe service are structured as follows:
The first time you make a request to subscribe, you get something like this:
This is a JSON array. The first is an array of messages—for the first request, it will be empty. The second entry is a string, and it is the new time token to use.
After the first request, you'll see something that looks more like this:
[[ "Some message here", "Another message here" ], "13782280489181345"]
Now, the first entry isn't full. It's an array of strings (in fact, these are JSON data which means they can hold any data you want, but ...