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
The traveller may shorten his prayers even if he is not encountering any difficulty

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Related Answers:
If a traveller decides to return part way through his journey, can he still shorten his prayers on his way back?
Can a person shorten his prayer before leaving his city?
Can a person who travels and stays somewhere for one day join and shorten his prayers?
Traveller should make his prayers complete if he intends to stay more than 4 days
The traveller may shorten his prayers even if he is not encountering any difficulty

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