Hey there,
I stumbled upon a thing where I can't cycle to last held weapon after using an ability. I don't know if this occurs with every ability but playing Jett, this is a big problem.
For example, when I have a primary weapon equipped, then equip a knife to run faster and jump up a crate using my Q then I'm stuck with the knife on top of the crate and can't use the Equip Last Used Item option.