DOT Hours of service rules apply to anytime time spent working. The manager has an obligation to know. You have an obligation to report any other employment and not be on road if you have not had 10 hours off.
On duty time means all time from the time a driver begins to work or is required to be in readiness to work until the time the driver is relieved from work and all responsibility for performing work. On duty time shall include:
8) Performing any other work in the capacity, employ, or service of a motor carrier; and
9) Performing any compensated work for a person who is not a motor carrier.
You are right, only this section is applied in the FMCSA rulebook, which also states that these rules are applying to drivers of a CMV (Commercial Motor Vehicle). Are vans or package cars considered CMV's, hence subject to DOT regs and the driver also subject to DOT regs, such as a CDL?
The FMCSA rulebook states that a CMV is considered a vehicle with a GVW of 26,0001 pounds and over.
Most air cars are simply that, a CAR! Some are vans, some are outright trucks! But, IN MOST CASES, (alright, you in different areas that may have strickter state laws respond and call me a dummy) package drivers are not required to have a CDL.
Now, if you're a part-timer at UPS, even a job driving an air car, and possess a CDL and go to work full-time during the day or night driving for a different company, THEN the rules apply!
If this is what the MGR was inquiring about, he STILL didn't have a valid case. His concern should be ONLY about your bid, your employ at UPS and ONLY if you completed your assigned job and were NOT required to go back out when asked! He is NOT required to keep track of your DOT operations for another company!
When asked such questions in the future, respectfully decline to answer any such that you feel are not pertinent to the operation. Remember tho, DO NOT refuse to work if you are still in your bid operation, your bid time, your bid job or if your bid also says that you must work mandatory overtime. You feel you have a problem, do the work, file later. Do NOT risk getting fired over semantics.