The baking time will depend on how thick/thin you made the sushki, your oven and also how crunchy you prefer the sushki to be. I like mine on the crunchy side, so I made them thin and baked them longer too. If you make them a little bit thicker, they will be softer.
To save time, you can simply roll the dough into thin ropes and bake them into sticks. Much faster, same taste, but of course, they won't have the "sushki" look.