The phrase "next newsletter" refers to the upcoming edition of a regularly published communication that shares news, updates, or information on a specific topic, usually sent out to a group of people via email or post. Full definition
«Our next newsletter will cover V1 in more detail and share some of the thinking, processes and designers who collaborated on what we reckon is powerful and important step in the way we take our vision of a new food system to the world». (afsa.org.au)
More about that in the next newsletter. (sport.ox.ac.uk)
Look for that in the next newsletter and on the OKAPT website. (oka4pt.com)