I have a Balsa strop that I purchased from the vendor that was already pasted with Chromium Oxide. I have used it approx. 6 times now to refresh the blade sharpeness of several of my straight razors.

My question is this: When should I re-paste my Balsa strop with CroOx so that it continues to refresh the sharpness of my straight razors' blades with maximum efficiency?

Thanks in advance for your advice/responses.