How so? Enabling the canary only tells you that one or more was served/obeyed, and can't be used again. To me, 0-999 also tells me that one or more was served/obeyed.

Is the rule actually 0-999? Because they'd have to get 1000 or more before you knew there was 1 or more.

It is four pages, the first page is mostly dedications and the last page is mostly blank. It will not take you much time to read the remaining two pages and develop your own understanding.

Here is how I am parsing it:

The Office of the Attorney General proposes two options:

1. Separate category reports for NSL, FISA content, and FISA non-content requests and customers affected.

2. A single report for all NSL and FISA requests, and a report for customers affected.

If you want to distinguish between the different kind of request (category 1) then you can report in blocks of 1,000, while if you don't, you can report in blocks of 250.

With how untested warrant canaries are in the courts, I wonder how a more detailed scheme would work. Every day making 1000 public statements, each of the form "We have received no more than N NSLs."

I don't think a court will be impressed with that.