These are mostly just a confusing relic from our now obsolete system of separate class sessions. They make recording attendance messy, and also encourage people to train too infrequently to make satisfactory progress (with very few exceptions).
So they are now going the way of the dodo.
Starting immediately they will no longer be offered to new students.
However, to help ease the transition, if any former student is eager to purchase one (or more) of the old 10/25/50/100 90 min class passes, you have until August 31st 2015 to do so.
From September 1st, only private packages or unlimited group training will be available.