@Torneng gave you the right advice, you can hover over the PL to get an idea why (example below):
Beyond that, best protocol for specifics on AT and your Progression Levels is always to check in with the support team.
They have the best visibility to the full scope of your internal ride logs and can provide some insight + make any changes if needed.
From the ‘Welcome to the TrainerRoad Forum’ Page:
Have a question about the app, your training plan, or device? Reach out to support@trainerroad.com instead of posting here. Our support team has the best visibility and insight into your devices, workouts and adaptations, and will help get you the most efficient and effective answer to your question.
Closing this thread up to keep the forum tidy from the multiple threads like this. 