Missing characters in Ultimate Comics: X-Men

It's disturbing seeing those two not appearing in Ultimate Comics: X-Men. We see Storm being a new addition along with Mach Two but where are Colossus and Johnny? Really? Storm and Colossus were in the same containment camp prior to the events of Divided We Stand/United We Fall and it's baffling how he wasn't in the Sentinel battle in UXM #18. Also, we see Johnny Storm in the same issue being found on the streets being "severely dehydrated and showing signs of horrific and sustained torture" then he has not appeared in issue 18.1 or 19. Apparently, he even got replaced with the Ultimate Version of Magma. And another thing, where are the other mutants; Pietro/Sabretooth/Mystique/Havok? Pietro and Havok were still there in earlier issues but after Brian Wood took over, we haven't seen them since and Sabretooth and Mystique's last appearances were from Ultimate X.