{TAIL ~ The control system} may update {HEAD ~ the shadow ledger} directly or interrogate the remote communications unit for an update after the remote ledger is updated 
{ TAIL ~ The control system } may update { HEAD ~ the shadow ledger } directly or interrogate the remote communications unit for an update after the remote ledger is updated
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH