I think celcom no longer provide this service, maybe port to MVNO that roam on Celcom network ?

altel with 90 day internet plan
xox mnp with season pass
redone basic 6 month contract
all above using celcom network

celcom prepaid credit advance still works but its not extended validity. Current new xpax does not have extended validity. If you still use older xpax then you still have EXP1 or EXP2 extended validity.

Else, for celcom mvnos :

1. need prepaid? check
2. need Celcom network? check
3. need extended validity? check

Here's the list:

1. Altel - 365days@rm28, pay-per-use@5sen/MB, 1GB/90days plan@rm25
2. Onexox - 28 months validity, 365days@rm25, no-pay-per-use, 500mb/30days plan @rm2.50 using season pass
3. Tunetalk - 365days@rm10(promo), pay-per-use@2sen/MB, monthly plans as per website