The lower pipelines may continue {HEAD ~ execution} until {TAIL ~ the mispredicted branch instruction confirms}, at which time all uncommitted instructions are flushed from the lower pipelines 
until
The lower pipelines may continue { HEAD ~ execution } until { TAIL ~ the mispredicted branch instruction confirms } , at which time all uncommitted instructions are flushed from the lower pipelines
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH