Thanks for the many replies 
I’ll attempt to answer the various questions in some sort of logical order:
Indeed, as @BlackDeath mentioned it’s a Minimum Viable Product, or in this instance intended to be the smallest combination of modules that would provide a workable synth (I noticed after I made the post above that I used a similar phrase in my inaugural November 2020 forum post while still figuring out what “minimum” meant in practice).
This is an important point and worth addressing: it’s absolutely my intention to make explicit reference and give full credit to Eddy, Sam, YuSynth, etc in the “v1.0” of anything I publish online. I never intended to share the v0.x schematics or PCBs publicly and only do so here so that I can (hopefully, finally) satisfy myself that they work (ideally by getting them to work myself) and then write up the project and share with others on the same journey. I work in open source software and I’m very much a champion of proper attribution and giving others permissive licenses to re-use my own contributions to the space (however modest).
Each project has its own PCB (the gerber files for the VCA and the ADSR are in the same repo as the schematics) and faceplate, both of which I got fabbed at JLCPCB (rather than use stripboard per my guitar pedal building days, I was inspired by one of Sam’s videos where he starts to convert his synth to PCB having had one-to-many equipment failures at gigs…)
As a reference, I’ve attached photos of the PCB and faceplate for the (happily, fully working) AS3340 VCO. The green terminal blocks connect the pots to the PCB (the numbers on the schematic should correspond to the lug number on the pot). The other modules are all built in the same style.
The designer(s) who designs the PCB layout uses the same set of design files to create the schematic (i.e. both are done at once), so I assume (but worth me checking) that if the schematic is correct, then the PCB layout is correct. Please say if this is a false assumption though.
I do.
“AD”?
