does anyone know if the following is possible?
Page A is linked to Page B (either via a property, editor etc). Is it possible to programmatically change the link from A->B to A->C ?
I've tried using IContentSoftLinkRepository but found that it doesn't always contain the linked content references.
Not sure if I understand you correctly, but IContentSoftLinkRepository is only for "soft" content link, like in a ContentArea.
This can be a start
Could you please provide more information about your query?