From this session S1, the client 20 can perform {TAIL ~ 610 changes} to the feature instances F1 and {HEAD ~ F2} 
From this session S1 , the client 20 can perform { TAIL ~ 610 changes } to the feature instances F1 and { HEAD ~ F2 }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD