During "Regenerate all", the book's page said most chapters were written although the rewrite had just started. Why?

Before version 1.9.22, the count included the old chapters still waiting their turn. From version 1.9.22, while "Regenerate all" runs, the Manuscript card counts only the chapters written again ("N/18 written again") and its progress bar matches, "Ready to publish" says "Rewriting: N of 18 chapters written again", and each chapter still waiting shows a clock ("Waiting to be written again: this is still the old text"). When the run ends, stops or fails, the marks are cleared.