Earnings data started to reveal signs of success for the plan in March, when Potbelly reported its first positive EBITDA since pre-pandemic. That measure — earnings before interest, taxes, depreciation and amortization — appears to have remained positive. Potbelly reported preliminary earnings for its second quarter last month, and adjusted EBITDA was $6 million to $7 million, up from $4 million during the same period in 2019. The company now has about 425 locations in the U.S., including 53 franchised shops. Potbelly has signed franchise agreements that equate to 81 new shop commitments.