It's always possible to keep your rebated plan even when you switch phones. However, it's possible that if you want the latest devices at their full rebate a minimum monthly amount will be required like @Jeffg1 mentionned.
You can see all of our current mobile devices here.
In order to have the exact answer in regards to your account, I would suggest you contact us by phone or go to one of our stores: Contact us
Thank you for your understanding!
Your Community Manager