Earlier this year it was announced to all congregations that the new silver songbook would ultimately be made of 150 songs, (matching the number of Psalms in the Bible). However, they've apparently changed there minds in the last few months, because songs 152-154 were just posted to both jw-org and jw broadcasting.
https://www.jw.org/en/whats-new/
Did you notice that there is no song 151 to be seen? It jumps from 150 to 152. I wonder if they're going to backpeddle now on releasing that deluxe silver softcover prototype they showed at the annual meeting, or if they'll even limit the number of songs in the revised songbook now . . .