How can I convert a return itinerary into one with stopovers?

I have found a return itinerary CWL > MEL > CWL, with connections in AMS and CAN. Outbound: 30th July, return: 10th August.

However, I would like to have stopovers in AMS - say, something like:

CWL > AMS: 23rd July
AMS > MEL: 30th July
MEL > AMS: 10th August
AMS > CWL: 30th August

(The CWL segments can be pretty flexible.)

So, I checked on ITA Matrix for the fare rules ("China Southern (CZ) L2KRCGB CWL to MEL"), and the relevant ones seem to be:

UNLIMITED STOPOVERS PERMITTED ON THE PRICING UNIT
TRAVEL FROM LAST INTERNATIONAL STOPOVER MUST COMMENCE NO EARLIER THAN THE FIRST SUN AFTER DEPARTURE OF THE FIRST INTERNATIONAL SECTOR.

But now if I do a multi-leg search on ITA Matrix, with a week or so stopover in AMS, I am offered only one option for AMS > MEL, on completely different flights (now KLM rather than China Southern).

I don't understand why all the options have disappeared.

Have I misunderstood the fare rules?
Why does a multi-leg search not include the numerous results included in a return journey search?
If there is a way to find a multi-leg fare with stopovers in AMS, based on my original return fare search, what do I need to do to find it?

stopovers ita-matrix

Best Answer

Without knowing the exact dates you're looking at it's impossible to say exactly what is occurring, but if I had to guess I'd say you're hitting an issue with what are called "Married Segments".

In order for a "fare" (eg, L2KRCGB) to be valid, you need to both meet the rules for that fare, AND there needs to be availability in the relevant fare classes for each leg of the trip. In your case, that likely means you need "L" class availability for each leg (it might be a different class, but for now lets just presume its L - even if it's something different the end result is the same).

Now obviously on the day you're looking, "L" is available all the way through.

So the first problem might be that when you change dates, "L" is not available on both the CWL-AMS and AMS-CAN-MEL segments. In that case, it'll jump it up to the higher fare.

However probably more likely what's happening is something called "Married Segments". With married segments, the fare availability isn't based on the individual legs, but on the end-to-end trip. Ie, the availability is for the "married" segments. Thus there might actually be no "L" class available CWL-AMS, or AMS-CAN, or CAN-MEL - but there WILL be availability when you book them as a single married segment CWL-AMS-CAN-MEL.

This is especially common when flights are across multiple airlines, as is the case here. The first leg you are looking at, CWL-AMS, is not flown by China Southern, and thus there's likely no L availability it when booked separately, but only when booked as a part of a larger, continuous trip. Adding in a stopover breaks that continuous trip, means that "L" is no longer available, and thus bumps you up to a higher, more expensive fare class.

Without more details that is just conjecture - but the fact that the ITA Software engine is jumping you to a higher fare means that there's something like this going on.