High consumer voltage is now the BIG problem.
Ten or twenty years ago the main voltage complaint from domestic customers to electricity suppliers was occasional or perhaps persistent low voltage. We developed the EC-1V, a single phase voltage logger to measure and record the delivered voltage. This was and is used by many power companies around the world. Many companies then wanted to also record the customer's current draw, to see if the voltage drop was caused by taking too much current. We recommend the EC-2VA for this.
Over voltages are generally caused or exacerbated by onsite or locally based renewable generation stations. The problems that over voltages can cause are tripping of solar inverters, solar hybrid inverters and battery charge and management systems and other sensitive onsite electronic equipment. Often affected devices are owned by the complainant, their first indication of a voltage problem.
If the complaint is over voltage, the recent phenomena, you can revert to voltage only recording, as it arguably not (as) important what the customer's current draw is! What is indeed relevant is whether or not the customer has (or is in the neighbourhood of) renewable generation, such as solar PV, wind turbine, hydro or other. It is also important for the electricity suppler to ensure that the onsite generation is turned off during the voltage logging period. This allows the actual delivered voltage to be recorded, uninfluenced by the local generation. If the customer's voltage is recorded with the embedded generation on, then the voltages recorded do not (not) represent the supplier's delivered voltage.
On occasions owners of embedded renewable generation stations are reluctant to turn off the generation as this is financially damaging to them, they will not get paid while they are not producing electricity and may have to purchase from the grid at unfavourable prices.
The network operator can't or won't measure the delivered voltage levels while the renewable station is generating (and possibly pushing the voltage higher), the customer is reluctant to turn the generation off, typically for a week to allow the network operator to measure the voltage.
My first suggestion is to measure the voltage on site with the station generating, this gives an indication of the extent (or otherwise) of the problem. Then based on that a conversation can be started with the network operator, but if the voltage is high the likely next step would necessitate the removal/stopping of generation for a week while the network operator records their delivered voltages.