Aircraft performance profiles, charts have high or low routes, low routes will depend on climb profiles and pressure, generally airlines and larger biz jets will be from 18,000 to 45,000 ft. Falcon 5X and the Gulfstream G650 all currently fly the highest with a service ceiling of 51,000 feet.
KATL Atlanta to KTPA is about an hour flight time. Get to top of decent then almost time to descend.