From Wikipedia <https://en.wikipedia.org/wiki/PCMag>:

>By its third issue PC was square-bound, because it was too thick for saddle-stitch. At first the magazine published new issues every two months, but became monthly as of the August 1982 issue, its fourth. In March 1983 a reader urged the magazine to consider switching to a biweekly schedule because of its thickness. Although the magazine replied to the reader's proposal with "Please say you're kidding about the bi-weekly schedule. Please?", after the December 1983 issue reached 800 pages in size, in 1984 PC began publishing new issues every two weeks, with each about 400 pages in size.

I don't believe BYTE ever reached 800 pages, but it came close. The only other computer magazine I know of that reached >400 pages per issue is ... 80 Micro, in 1982 and a special issue in 1983.[1] The magazine folded in 1988, which tells you just how quickly the TRS-80 market collapsed once the IBM PC (as represented by PC) got going.

[1] The special issue has an editorial titled "There's no end in sight". <https://archive.org/details/80-microcomputing-magazine-1983-...>