Ah - thanks for clarifying. But so the tester needs to keep going, not stop, when kiddo hits the maximum score correct? So still worth double-checking to make sure the tester will use extended norms as appropriate?
Basically, the tester just needs to use the actual stop criterion for the test. Some will stop before a child has missed the requisite number of items, because they "know" it won't make any difference to continue.
I personally would be too nervous about asking for extended norms before my child has taken the test the first time, because I would think it made me look like "that mom" too much. I would ask for the raw scores, and also ask if they used the stop criterion given by the test, if I saw a couple of 19s on the report.
