Called as I suspected potential mold. They were out the next morning to get it tested. Confirmed a few days later it was bad mold, explained the job and what was next. Worked around my schedule and came on time and completed the work promptly. The section of wall where the mold was looks good as new and the workers were great to deal with. Hopefully I never have to worry about mold again, but will certainly reach out to certified mold removal if I need to.