I had a friend who recently upgraded to the 9700 and was on the old BIS plan ($20/month). He said that because the 9700 has 3G, he also had to upgrade his data plan because the regular data plan wasn't 3G capable.
I also noticed on the Tmobile website that BIS is now $30/month. For those who upgraded, were you able to stick with your previous BIS plan or did you have to upgrade to the more expensive plan as well?
3G has nothing to do with BIS actually, other than the speed of the connection.They just moved him to the new BB data plan. Do as lacroixn suggests above and see if that works.