The quickest way is to look at your sync speed. If using a router log in and look at what speed you have sync'ed at. Your upstream should be obvious from the very second you have been upgraded as mine worked immediately.
The downstream on the other hand didnt change until BT had generated a report for my connection.
So in short, if upstream = greater than 288 ( ie 448 or higher ) then your on MAX ( please note if upstream is a lot higher then you may be on LLU ).