Right off the bat, we suspected the promotional T-Mobile ONE Unlimited 55+ plan was meant to be a limited-time thing. It was simply too cheap to last, allowing the “Un-carrier’s” existing and new postpaid customers aged 55 or older to get a pair of unlimited data lines for a measly grand total of $60 a month.

Everyone else has to pay $70 for a single T-Mobile ONE line, and an extra $50 for an additional line of service, so let’s not act shocked or outraged that the 55+ plan is due for a (small) price hike next week.

Namely, starting March 15, you’ll be asked to cough up $70 instead of $60 each month. There’s still time to get the offer at its introductory price, and if you’ve already signed up, fret not, as T-Mo will continue to charge the old rate.

Obviously, Unlimited 55+ plans come without complimentary Netflix, also limiting tethering to 3G speeds. Otherwise, you’re getting a heck of a deal, including unlimited talk, text and LTE data for yourself, plus a friend or family member whose age is of no importance.

Video streaming quality remains mediocre, at 480p, and “during congestion”, you may notice “reduced speeds” due to “data prioritization” if you tend to use up more than 50 gigs a month. Oh, and both the current $60 price and the impending $10 increase include $5 per line AutoPay discounts. Last but not least, keep in mind that the primary account holder has to provide proof of age to claim eligibility.