In this instance we are using an actual Consultant created Sabre PNR
Originally the consultant booked and Ticketed fight for 3 pax
everything imported correctly in the first instance
THEN
their Client decided they wanted to change the return date from Stockholm to Adelaide
remember all of theses sector were already Ticketed
The consultant created TWO new legs in the PNR (with NO PQ so unticketed) there should have been THREE New legs
Next the Consultant Updated the PNR selecting the following Options

The when prompted in the next Modal selected the following

the result of this was the following and an associated itinerary nightmare

what should have happened next was for the consultant to reissue / ticket the last three legs of the Itinerary
THEN
when processing the Update Select as follows

The result when doing the above is as follows

The original legs are retained with only the associated Ticketed itinerary legs updated
What we have learned from this is the following
If segments are NOT required anymore - REMOVE them from the PNR and ensure you do a PQ or TST or the like for the required sectors.
NOTE: ALL itinerary Legs when being Imports NEED an associated trip sector / ticket number / Pax