The value of msapTlsPlcyIgmpSnpgLastMembIntvl specifies the
Max Response Time (in tenths of a second) used in
Group-Specific and Group-Source-Specific Queries sent in response
to 'leave' messages. This is also the amount of time between
Group-Specific Query messages.
This value may be tuned to modify the leave latency of the network.
A reduced value results in reduced time to detect the loss of the last
member of a group.