I received the SMS to upgrade from iValue 1 to MOP98. As suggested by ^Ware^Wolf earlier to communicate with Maxis via twitter, I did the same and I have switched to MOP98 with 5 Gb data. According to the person I chatted with, my current contract is untouched, i.e. I will still have to honour the original duration. Everything else stays the same, including autodebit details.

Will report back if I face any problems. Thanks for the tip again, mr Ware Wolf.