I just noticed that the blogroll links weren’t showing up properly on the sidebar. Then it all clicked - I’d also wondered a few days back where the ‘Links’ link was in the admin panel, and that there was a new tab called ‘Blogroll’.

This all led to me searching for get_links and wordpress leading me to look at the WordPress Support post about this particular problem. You need to remove the quotes from around the category number - and also change that to the cat_id - WombatNation and the City of Rain have written about this.