1 Gig plan cart charges $30 for "Unlimited Data" that's listed as included

I'm an existing customer with my own modem, currently on a legacy Gigabit plan at $154/mo ($124 + $30 Unlimited Data add-on). I'd like to switch to the current 1 Gig plan, but when I added it to my cart, the cart contradicted itself:

• 1 Gig: $110.00/mo
• Unlimited Data: $30.00/mo
• Customer Owned Equipment: $0.00/mo
• "Included with plan: Unlimited Data"
• Autopay & Paperless discount: -$10.00/mo
• Estimated monthly total: $130.00/mo

The site banner also says: "Enjoy equipment and unlimited data included at no extra cost when you choose from our newest plans."

1. With my own modem, is unlimited data included in the $110, or is it an extra $30?
2. As a customer since 2013, am I eligible for 1 Gig with the 5-Year Price Guarantee, and at what price with my own modem?