iPad 3G Data Service Explained before Friday's 3G iPad Launch
In addition to details posted last month by Apple on how 3G data service will be managed on Wi-Fi + 3G iPad models due for launch this Friday, AT&T has now published a fact sheet (PDF) offering additional information on iPad data service.
AT&T notes that its "monthly" domestic service plans actually consist of 30-day cycles that will automatically renew unless the customer elects to cancel his or her contract-free service.
Customers who reach their data limit for a billing cycle can either wait until the end of the 30-day cycle when it automatically renews or change to an unlimited plan, which will begin a new 30-day cycle at that time.
You do not switch from a 250MB to Unlimited Data by only paying another $15 when your 250 MB runs out. If you opted to pay only another $15 you only start another 250MB data plan. If you blow through that in a couple of weeks you will have ended up spending $30 for only a half gigabyte of data when you could have had UNLIMITED for the same amount of money in a four week period.