Voltage rise from the service point to the inverter is specific to your site, depending on the size of your wiring and the current your inverter is producing. So a neighborhood slight voltage rise could bump your system outside the operational window if your site-specific voltage rise is on the high end. [Occasionally the cause of site specific voltage rise can be a mediocre connection somewhere between the service point and the inverter, causing extra resistance.]
Anyway, the usual utility reconnection timer is 5 minutes, so the thing to check is whether the inverter production goes to zero for 5 minutes or more. Does the inverter have any logs that you could check to see if the grid voltage it sees is spiking?
Cheers, Wayne