Sprint Free Year Promo - new phones

So, you CAN upgrade to a new subsidized phone without losing the plan?


When can I upgrade to a new phone on this promotion?
Upgrades for the lines activated on the Free Unlimited plan will be allowed after 4 months of service. At that time, return to sprint.com and log in to your account to purchase/lease your new phone. When it arrives, visit Activate your device to activate the new phone. Any upgrades prior to the 4 months or in a retail location will require a plan change to the Unlimited data, talk and text plan which starts at $60 per month after an AutoPay discount. Unfortunately, you’ll lose the remaining free months in your year of free service if you upgrade early or purchase/lease your new phone in a retail location.

I believe that's always been the rule. (Yes, you can buy a phone from the Sprint store after the initial period.) Your Sprint dashboard will show when you're eligible for a device "upgrade".
Beware of the usual issues with Sprint regarding how payments are configured, since only some allow you to pay off the phone in full anytime you want at the subsidized price.

I've looked from time to time, but with the exception of the Essential promo, I've never seen anything very temptimg. (But flagships are out of my price range, so they're not likely to tempt me regardless.)