User blog comment:Supahbadmarine/Official Canon Policy/@comment-3341288-20130222153207/@comment-9465750-20130223094717

Well, now days it is ok for a chapter to be split into a warband and 100-500 men chapter. The loyalists of that chapter would still exist and their gene-seed would still be used.

On alien tech: we need to note that there is nothing more advanced than warp drives, thus, you can have them or something weaker. As for weapons, dont push beyond Tau/Imperial tech......