As I understanding, leaving the starter at room temperature and only feeding it once a week is not feasible. What I do is keep it in the fridge, then pull it out at room temp when I'm thinking about a loaf. I feed it two to three times before making a levain, and toss it back into the fridge after I replace the flour and water from the levain pull.
This was the first time I had heard of it as well. Also, I wassn't clear on once-a-week required refrigeration. To the fridge it goes, then. Attempting a banana-bread sourdough tonight.
Good luck to your loaves!