newboy wrote:
Does anyone know how to separate such a system from the lid, or what
I’m missing (probably simple) or are they really designed so that if
it’s removed it has to be broken and the whole thing replaced?

I've one of these I think; on mine there's a little chain which you have
to unhook to let you remove the lid. Very fiddly, you have to squeeze
your fingers in through a small gap. Hate it!

David