Processing from {HEAD ~ either process block} 1140 or process block 1150 terminates at {TAIL ~ END block} 1155 
terminates at
Processing from { HEAD ~ either process block } 1140 or process block 1150 terminates at { TAIL ~ END block } 1155
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH