This read-only PerfCounter64 counts reflector-to-probe available delta_ts, incrementing when FLR is at or below the availability threshold for 'n' consecutive delta_ts, per its description, the return-direction counterpart to f3EsaProbeStatsSoamPmExtP2rAvailableDeltaTs. An administrator uses it to determine return-path availability under the standard SOAM-PM delta_ts naming, complementing whichever forward-direction object their tooling reads. For example, an operator auditing return-path availability against a standards-based SOAM-PM tool would read f3EsaProbeStatsSoamPmExtR2pAvailableDeltaTs rather than the vendor-specific AvailableTime object.