Revise printed Booke. Introduce vestigial copyright page and move instroduction before the contents, so on A4 it appears on the verso to the content recto. Tunes then start double page spread on the next page. Add a \cleardoublepage before the index of first lines to force that to start on a new double page. This minimises the page turning necessary to see all the index lines.

\documentclass[a4paper,11pt,openany]{book}