You cannot use it that way, as stated in your contract. You will get terminated, if they find out.

Never try before.. I think should able to use, if not why the installer want to take out the sim.

I take Maxis almost 2 month to handle my case.

Maxis people only check from they system.. and only based on their system.

At first Maxis want to close my case mention that the sim is active and being use, and play the blaming game mention that I have sign the form and the sim card should given to me.
They only offer me with the card replacement after i scold them kau kau.

Same day their "Installation Department" (I forgot what the department name already) they want to double confirm the status and check back with the Installer then the next day the installer (who dont want to pickup my phone after I asking asking about the Sim Card) call me asking whether I complaint to Maxis and offer to come over my office to check the router.

Day after, he come to check and try to insert the sim card "silently". As I standing in front the router all the time, He have no choose but take out the sim card from his pocket and say he forgot to insert the sim card.

**
If the backup line is not the deal breaker for your, avoid using Maxis Fiber. I got 3 branch office using Maxis FIber, All Branch having issue with their Installer.  Best sorry is My JB office line down,  they only sent their people to check after 1 week and also play the blaming game saying is the TM issue.. but at the same time their backup line is down for 1 week..

The new router something will hang..
need to restart.. other then that is okay..

But my JB office still on and off got connection issue and the backup line do nothing.

Fibre from TM --> TM Fiber Modem

Internet From Maxis --> Maxis Router

Modem from TM.. it stable..

Router hang about 1 time for a month.. need to restart..