The schedule change "due to customer service" is probably a euphemism for, something liiike, ... the G/A took an emergency leave....
Really I want to read another example of what "due to customer service" might mean in real life.

Last Saturday I was scheduled to go on a flight (6853) that was cancelled without any excuse on the flight status page. Let me say that the weather was BEAUTIFUL in both ends of the route. So really this pitiful excuse was unavailable.
But. I speculate that the flight was cancelled becuase of low occupancy - insufficient pax. Just 5 of them.
Obviously no apology, no nothing from UA/UX.
May be soon we shall read something like: "flight cancelled due to insufficient passengers." And the contract of carriage will be amended to say: "management reserves the right to cancel any flight that in its opinion is not profitable."