They travelled for twenty days during which they shortened their prayers. Do they have to make them up?

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Check below answers in case you are looking for other related questions:
Traveller should make his prayers complete if he intends to stay more than 4 days
Can a person shorten his prayer before leaving his city?

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Related Answers:
Shortening the prayer when traveling without specific destination
Combining two prayers before travelling
The one who takes a short trip to a city where he has a relative is considered to be a traveler
Traveller should make his prayers complete if he intends to stay more than 4 days
Can a person shorten his prayer before leaving his city?

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