Just seeing those covers gave me a huge nostalgia-trip, from my own time programming the ZX Spectrum in the 80s. (First in BASIC, then in Z80 assembly via the fine manual.)
No, that's something I don't think I've ever seen before.
I used to read a few of the Spectrum magazines back in the day, Your Sinclair, Sinclair User, etc. But over time they all dumbed down and started to be more about advertising and game-reviews, rather than having a mixture of programming-content and other stuff.
I did get some POKEs printed though, so it wasn't all bad!
Have you also used the Input magazines?
https://en.wikipedia.org/wiki/Input_(magazine)