This read-write value, in UTC, records the last time the PPPoE statistics counters (session and PAD-packet counts) were reset. An admin reads it to know how long the current counter values have been accumulating, which matters for interpreting rate-of-change in the various PADI/PADR/PADS/PADT counters. For example, checking usrPPPoECounterResetTime before comparing usrPPPoENumberPADIReceived across two polls confirms whether the counters were reset in between, which would otherwise make the comparison misleading.