Complex sentence: They were slated to become the full time sponsor of Andretti in 2017 and sponsored them at St. Petersburg but when the company closed, the team removed their logos on their cars but remained on the firesuits.
Split into simpler sentences: They were slated to become the full time sponsor of Andretti in 2017, and sponsored them at St. Petersburg. When the company closed, the team removed their logos on their cars, although the logo remained on the firesuits.