The utility I work at set the limits for voltage at 95% to 105% or 114 to 126 for a 120v feed, we measure the voltage at the line side lugs of the meter socket.
I'm curious is the service is 120/240 & if so, what is the line to line voltage? I've seen weak nuetral connections cause the voltage on the lightly loaded leg increase to 130 - 135 and the voltage on the heavily loaded voltage drop to 105 - 110.
At our utility, a high voltage or low voltage complaints are resolved as soon as possible, if not same day, due to the damage that can be done to the customer's equipment. Also, most public service commisions require the utility to provide "correct voltage" to a customer or be responsible for damages. (We interpret correct voltage as the above stated range.)
