Originally Posted by Jason100:
“I'm currently with T-Mobile/EE and upgraded to a sim only plan on the same number today. Will my current pay monthly plan end once I activate the new sim card? I already have outright bought my new phone.”
The name of the network on the screen is always EE, but you may have been on an Orange or T-mobile SIM and price plan in the past. If you were with Tmobile and have now migrated to EE and had a new SIM card for EE then the Tmobile SIM will stop working when you activate the EE SIM.
The only reason you need a new SIM is generally to move from Tmobile (or Orange) to EE to get the benefits of 4G. If you are just changing price plan then you don't get a new SIM.