I don't give mine baking soda unless they need it but a lot of people do free choice. With the Vitamin B & calcium drench you sound prepared. Your local extension service should be able to clue you in on the selenium needs in your area. I didn't have mineral issues until after our 2016 floods, that really changed things. Selenium deficiency is coupled with Vitamin E deficiency and many breeders give BoSe shots to new mamas, BoSe has to be gotten from a vet. The OTC remedy is Selenium/Vit.E gel.
