1. You can register maximum 10 account per ID card. Not 10 account per Telco.
2. Usually after 90 days cooling period, Telco will terminate their services if user didnt reload their prepaid sim. They will re-use that number for new simcard. If you still sayang that number you can go to their customer service center and ask the officire to check if your number still in the systems. If still in, so you're lucky.

Last time my celcom prepaid been terminated, and a wee later I go to celcom service center. I ask the pegawai, luckily my old number still in the system. so the pegawai ask me to pay rm30 as reload token to re-activate the simcard. Rm30 I paid been credited into my account, as airtime credit..

so the expired number will not count towards the 10 number limit right?