As far as I know so long as it's just pure hay (no coloring, flavoring, treats mixed in, etc.) any type is fine to switch out with. I normally buy a bag of timothy and a bag of something else, oat, orchard, or meadow (whichever happens to look good). I've also heard that it's good to offer different types of hay because each type wears down there teeth differently, but don't stop giving timothy hay it's high in fiber and low in calories. If your pellets are alfalfa based and it's not a baby or mother it's best to only give alfalfa hay as a treat so you don't end up with a fat furball, my guys get a cube each every week or two. The botanical hay tend to have treats/herbs mixed in, the Oxbow botanical hay for example has "Timothy Grass Hay and three of the following herbs depending on seasonal changes: Chamomile, Lemon Verbena, Hibiscus, Lavender, Rose Hips, Comfrey, Borage, Red Clover Blossoms." for ingredients, so basically timothy hay with herbs, and since it's timothy as the actual hay and you wanted something different for hay I'm not sure it's worth it, I'd rather just give my guys treats separate anyway, they might dig though the hay to get to the herbs.