No one can answer this question without a thorough inspection [both visually and careful poking with a probe (such as a fingernail, pencil, or screwdriver)]. So you should have them checked out by a skate tech. Also depends on your level of skating, particularly spins and jumps. With sole rot, an immediate concern is the screws not being firmly anchored and the blades becoming loose or even detached. So at least check to see whether your screws are tight. I check my screws before each session.
A proper inspection will also require that the blades be removed to get a good look at the areas of the sole under the sole plate and heel plate. Even though the plates may appear to be nominally flush, water can still seep in (besides which, water can still seep in under the plates from the areas of the sole outside the plates).
Did you know what protectant was initially applied [especially if you bought them used, you might not know the history]? What protectant did you apply? In general, you don't want to mix two different types. Also, when you did your application, did you remove the blades first?
Do the brown flecks appear to be chunks of leather or flakes of varnish or paint?
And, as in the other thread, are you drying your skates thoroughly?
What boots (make and model) are they? At one time I followed the recommendation of one coach (who also sold skates as a sideline) and didn't apply any protectant to the boots (Riedell Royal at the time; we're talking about relatively high-end boots with some degree of factory treatment, not totally untreated leather). I had no problem with premature sole rot (the uppers wore out first). But I'm very scrupulous about drying off my boots and blades thoroughly. And I don't skate on ice with water puddles either.