Is My Job’s Pay Structure Compliant With Flsa? [ky-usa]

I'm trying to understand how the DOL-FLSA applies to my job. Several coworkers and I suspect that our pay structure might be unfair or potentially illegal, but we aren’t certain. Below is a breakdown of how my compensation works, including descriptions and examples. If more details are needed, please let me know, and I’ll update the post.

Monthly Retainer: ~$2,000 The company classifies this as a "retainer" on my paystub. It is meant to compensate for up to 21 hours per week in the office, which covers: maintenance of equipment and the restocking job supplies. Also, this is meant to compensate for driving time to and from field sites. These 21 hours in the office are not paid at an hourly rate but do count toward overtime.

Example: If I spend 14 hours on equipment maintenance and 36 hours working in the field during the same week, I’ll be paid for 26 hours at regular pay and 10 hours at the overtime rate.

Hourly Pay: $20/hour This rate is only paid for time spent on location at field sites.

On-Call Requirements I am required to be on call 24/7/365. This means I must: Answer my phone at any time, day or night, be at the office and ready to travel within one hour. If I plan to be farther than one hour from the office, I must take a PTO day (8 hours), which Is not paid at an hourly rate, and does not count toward the 21 hours of office time covered by the retainer.

Travel Time Travel time is not compensated and does not count toward overtime.

Example: If I drive 8 hours (16 hours round trip) to a field site in a company vehicle and work 9 hours at the site, I am only paid for the 9 hours worked at the site.

Another Example: One week, I drove a total of 32 hours, worked 24 hours at a field site, spent 7 hours at the office, and stayed in a hotel for 4 nights. My paycheck for that week included the $2,000 retainer and 24 hours of regular pay.

Does this structure violate FLSA? I would appreciate any guidance.