The older, "50% off" deal, was introduced in November 2015, undercutting Verizon, AT&T and T-Mobile plans at half off. The offer was valid until January 8, 2018, so next billing cycle could be a pain. "Unlimited freedom," on the other hand, gives five lines of unlimited data at $20 apiece, but has an expiry date of January 31st, after which you'd be paying extra $30 per month.
Analysts are even baking in a higher churn rate for Sprint in this quarter, due to the possibility of customers getting surprised by the price increases, and flocking to other carriers. Sprint is known to extend its promos in the last minute, but this might not be the case this time, as per its spokesperson quote above, so we'll see how many of its subscribers will be affected by the expiration of "Unlimited Freedom" and "50% off" this month.
source: Fierce Wireless