Page URLs and page contentIds
An important aspect is that during the publishing action from the new source space to a target space an page link to another page in the source space is updated on the published target space page to the destination page in the target space (if published).
The published page link URL is changed to
the target space key (by the Comala Publishing app)
the link destination page contentId in the target space (by Confluence Cloud)
Original page URL in the source space
/wiki/spaces/PROD/pages/2438561796/Product+Team+Ethos
Published page URL in the target space
/wiki/spaces/DEV/pages/2438693479/Product+Team+Ethos
Published page URL in the target space with new contentId
/wiki/spaces/PROD/pages/2438823986/Product+Team+Ethos