Hello Meg, I am glad to help you sort this out so you can finish your meal prep smoothly.
To substitute baking powder for baking soda, the standard conversion ratio is 3:1. This means that for every 1 teaspoon of baking soda called for in your recipe, you should use 3 teaspoons (equivalent to 1 tablespoon) of baking powder. Chemically speaking, baking soda is pure sodium bicarbonate, whereas baking powder is a blend of sodium bicarbonate, an acidifying agent, and a starch stabilizer. Because the active leavening agent is diluted in baking powder, you need three times the amount to achieve an equivalent rise and airy texture.
Regarding the yogurt you added: in the original recipe, the natural lactic acid in the yogurt serves to neutralize and activate the alkaline baking soda. Because baking powder already contains its own dry acid component, it does not rely on external acidity to produce carbon dioxide. The presence of the yogurt will not hinder the leavening reaction, nor will it ruin the bread. In fact, yogurt contributes fantastic moisture and tenderizes the crumb structure. The only minor difference you might notice is that baking soda produces a slightly darker crust through alkaline-promoted browning, so a loaf made with baking powder may look slightly paler.
One important practical tip for your meal prep: commercial baking powder is usually double-acting, meaning it begins reacting the moment it gets wet and finishes reacting in the heat of the oven. If your plan is to freeze raw batter, some of that initial leavening gas may dissipate over time. For the best rise and texture, I recommend baking the entire batch first, letting the loaves cool completely, and then freezing individual slices or mini loaves.
I hope this explanation gives you the confidence to finish up your batch!