I believe once you max your data for your plan then thats it - you get no more data. You are not able to exceed past your plans data limit. This topic is being discussed here :http://productioncommunity.publicmobile.ca/t5/Public-Lab/Throttle-instead-...
The promo is still active however they are not promoting anymore. When you activate your sim and then choose to create a plan - select the Fall 2016 promo on the right side and it should automatically set your talk,text & data to the promo as well as...