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https://www.wellscityharriers.org.uk/70-uncategorised/1218-street-5k-race-2-november

New link style
https://www.wellscityharriers.org.uk/index.php?view=article&id=1218:street-5k-race-2-november&catid=70

...so you need to change the structure to

https://www.wellscityharriers.org.uk/index.php?view-article&id=articlenumber:name-of-article&catid=70

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