Worn Tattoo levels up on its own, wasn't so always (in General)

I distinctly remember a few months ago the tattoo worn on my character increased its level only when I trained the exp. However, nowadays, at least since a few weeks ago, I notice that the worn tattoo gains level through the fights, without having to train the exp.

Have we missed out on this "insignificant" change?

always was this way, tat's train when flush comes around or you unequip

Tats train as exp is gained. There is no waiting for training, cache flush or anything else.