As Atheling aka Darrell has posted previously, it is a good idea to allow the polyurethane gloss varnishes such as Humbrol 35 a week to fully cure otherwise there seems to be some ‘blending’ of the two.
I was in a rush with one batch of figures, waited a week and then applied the Matt varnish and put them on a radiator to help speed up the drying.
They ended up with a satin finish 😣.
Had to wait another week before applying the matt again.