Personal Hotspot/Tethering iPhone 4 in non 3G coverage area

[Anonymous]

I am getting moved onto the new tariff that allows tethering on 3 April. Because I want to be able to occasionally use my wifi only iPad in a non wifi area, so the new tariff is ideal for me has it works out cheaper than to purchase a 3G & wifi iPad (which is £100 more expensive than the wifi only version plus the cost of a data tariff for it too).
I was wondering, is it possible to still Personal Hotspot/Tether when you are in a non 3G coverage area, i.e. EDGE, GPRS coverage only?

[Anonymous]

My dad called them last night o. Behalf of me because I am deaf. The person said they can't change it till July because my agreement. I am on 24 months from July 2012. He also states that the price wil go down to £31 a month starting July. Then down another step(tariff) an year later. You can only go down 1 step each year.