I've updated The Missive to version 2 on DriveThruRPG and itch.io, since there were some editing-related issues and a couple other things I wanted to address.
In addition to editing, I made some slight clarification tweaks, changed how Hazards are added (any failure, instead of repeated failure) and made the Integrity mechanic more clear. The GM section has been heavily tweaked and revised, but I did a line-edit across the whole document other than the opening fiction. I didn't touch the example text because I felt like it was satisfactory, but I did review it to make sure.
A happy accident is that this reduced some of the file-size, though I'm not 100% sure why. I know there was an Affinity update since I first published The Missive, so presumably they changed something with their PDF exports, or maybe I just used a slightly different workflow to get the PDFs out.
I think I exported the first version as spreads and then split the PDF into pages from those spreads (so page 1 and 2 were on one page until I split them, for instance), while the second was exported directly as pages. I'm not sure if that would make a difference, but it definitely seems to have helped a little.
It's not really noticeable in the main PDF (turns out 17x11 images at 300dpi tend to eat up memory like nobody's business), but in the print-friendly versions there's about a ~90% difference, which is cool. I could probably have gotten the size a tad lower, but it didn't seem worth nit-picking.