That's fair. At the time I thought it might be because they were struggling to deal with both the Andrew situation and the Harry drama simultaneously, while Charles was generally more unpopular than his mother, and likely ill.
But if they privately found out something that made the Andrew situation untenable, it makes sense that they would try to distance that ASAP. I wonder whether it's something that has been released already or is even worse.
Charles' statement today on "we support the police", plus letting them search The Lodge, definitely feels like they're leaving him to rot. At least maybe a little.

They have to, this was for pre-charge questioning, and they have time limits on custody for that. They've also searched 3 of his properties and his former residence. The question now is when and if they formally charge him.