According to QR rules, they take the highest of Change/Refund and No Show fee, not both :
NO-SHOW
A PASSENGER FAILS TO CHANGE/CANCEL HIS/HER
RESERVATION 3 HOURS PRIOR TO DEPARTURE ANY RE-
BOOKING MADE WITHIN 3 HOURS PRIOR TO
DEPARTURE OR AFTER DEPARTURE OF FLIGHT AS SHOWN
IN THE E-TICKET WILL BE CONSIDERED AS A NO-SHOW.
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FOR A SCENARIO WHERE IN THE ORIGINAL RESERVATION
IS CANCELLED PRIOR TO NO-SHOW CONDITION BUT THE
NEW RESERVATION ARE MADE AFTER DEPARTURE OF THE
FLIGHT AS MENTIONED IN E- TICKET COUPON
RESERVATION AND TICKETING STAFF MAY PERFORM A
MANUAL TRANSACTION WITHOUT ATC ENTRIES TO AVOID
THE COLLECTION OF NO-SHOW FEE
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CHANGES AGAINST NO SHOW
- IN CASE OF NO-SHOW ONLY ONE FEE IS TO BE CHARGED
I.E. EITHER THE NO-SHOW FEE OR THE
REISSUE/REVALIDATION FEE WHICHEVER IS HIGHER AND
NOT BOTH.
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CANCELLATION / REFUNDS AGAINST NO SHOW
- IN CASE OF NO-SHOW ONLY ONE FEE IS TO BE CHARGED
I.E. EITHER THE NO-SHOW FEE OR THE
CANCELLATION/REFUND FEE WHICHEVER IS HIGHER AND
NOT BOTH.
If you intend to miss the last leg of your trip, you have to take into consideration that recent addition to the rules :
PASSENGER SELF OFFLOAD DECISION REFUSAL OF
FURTHER TRANSPORTATION
IF AFTER CHECK-IN YOU AND OR ANY PASSENGER
ACCOMPANYING YOU DECIDE NOT TO TRAVEL ON A QATAR
AIRWAYS SERVICE WITHOUT A VALID REASON AND INFORM
US LESS THAN THREE HOURS PRIOR TO THE FLIGHT
DEPARTURE THEN THE FOLLOWING WILL APPLY
A. IF THERE IS A FLIGHT DELAY AS A RESULT OF YOUR
DECISION THEN WE RESERVE THE RIGHT TO RECOVER
FROM YOU ANY AND ALL DIRECT COSTS INCURRED DUE TO
DISRUPTED OPERATIONS WHICH INCLUDE REMOVAL OF
YOUR BAGGAGE FLIGHT DELAY DISRUPTIONS AND
MISCONNECTIONS OF OTHER PASSENGERS. IN ADDITION
WE WILL CANCEL YOUR ENTIRE TICKET FOR ANY FURTHER
TRANSPORTATION WITH NO REFUNDS.
B. IF YOU INFORM US BETWEEN 3 TO 2 HOURS PRIOR
FLIGHT DEPARTURE TO OFFLOAD YOURSELF ON THE
BOOKED FLIGHT S AND IF THIS DOES NOT RESULT IN
ANY FLIGHT DELAY DISRUPTIONS OR INCONVENIENCE TO
OTHER PASSENGERS THEN WE MAY PERMIT CHANGES TO
YOUR TICKET BASED ON THE APPLICABLE FARE RULES. A
CHARGE WILL HOWEVER APPLY WHICH WILL BE EITHER
THE NO-SHOW FEE OF THE RESPECTIVE FARE TYPE OR
USD 150 WHICHEVER IS HIGHER