my brother and i both have unlimited data, on a plan with our mom who has a dumb phone. we have 1 upgrade ready and then another coming in august. he got the S3 when it came out and im going to grab the S4. whenever we have an upgrade, we are going to transfer the upgrade to her line, upgrade her line. deactivate it, turn her old dumb phone back on, get rid of the tiered data pack and then activate the S4 on my line.
some people mentioned here doing the upgrade on your line but when the phone comes activating the phone on the dumb phone line but i would suggest just transferring the upgrade to the dumb phone. dont get your main line involved at all.
Samsung Galaxy Note 10.1 2014 Edition 32GB - Rooted
Samsung Galaxy S4 16GB - CM Nightlies
Samsung Galaxy Nexus VZW - Gone
Nexus 7 2012 32GB - Gone
HTC Thunderbolt - Gone
Motorola OG Droid - Gone