unlocking and using sprint

i asked a question like this question earlier, but here's a follow up question:

so currently i have an iphone5 on my sprint contract. if i change my phone to an old flip phone i have, and continue my contract, can i ask sprint to unlock the iphone5 i have? my contract is with my line on sprint right? so therefore i still have an active line, just need the phone unlocked, so i can use it with verizon.