Not entirely correct. This was what happened to me this morning :
1. I called up the CS at 123 and told them I wanted to speak with the loyalty team because I was seriously intending to port out but not yet initiated the porting process.
2. They did the standard account verification, created a ticket and told me someone from the Maxis would call me later.
3. Then, in the afternoon I received the call, and the guy introduced himself from Maxis and discussed about my intention to port out.
4. He then asked about how much data I wanted and presented the various available (read "counter") plans.
5. One of them is the RM68 with 5GB with unlimited call and SMS, valid for two years/24 months and no contract. Basically it's just the RM158 OnePlan with RM90 rebated over 24 months. Same goes for the RM188 OnePlan with RM100 rebate.
6. He further stated that during the 24 months period, I'm free to change plan or port out and there will no penalty imposed.
7. I asked for email confirmation on these T&C, he responded "can't spell these out in email" but such will be reflected in the new bill.
8. I accepted the offer, but since I was still with contract on the existing plan, I was told to pay up the remaining termination penalty cost first.
9 He then activated the new RM68 plan for me
So, bottomline you just need to call up the CS and take it from there.
Yes, you can. Just pay up the remaining termination penalty cost and you'll be OK.
P/S:The CS @ 123 will pretend to tell you there is no "loyalty team", however you just need to insist

Thanks for the info bro. Your previous plan with maxis is what?