They also move at about the same rate! So...very...slowly.
Hmm. In sheer page count... Green does 4 pages a week, so about 200 pages a year. That's slow compared to pro mangaka ruining their health, but 16 pages a month is pretty good for a Western webcomic. 91 chapters so far, so 364 pages.
Blue Star the past couple years has been doing about 3 chapters a year, of like 35-45 page lengths. Some of the earlier chapters were more like 20 pages, though... One could say 17*30 = 510 pages as a lower bound, huh.
For major event timing, (Blue Star spoilers): one-way confession by the end of chapter 7, so like 210 pages, Green hasn't gotten there, hell Green hasn't had 100% confirmation of romantic feelings even. Blue Star took under 30 pages for Umi to be lustfully gaaaaaay. 19 pages for her to freak out at seeing Shou's bra.
So, Blue Star feels slow because we get 3 big chapters over winter and then have to waiiit. And it is slower than a weekly manga or even a 20-page monthly one. Greenie has modest regular output, but we're at the equivalent of 9-18 longer chapters (40-20 pages), and we're arguably still in the subtext zone. Which, I dunno, maybe isn't that slow. Definitely slower than some, though.