People seem to not understand what a scene release group is.
Duplex is a scene release group. Their goal is piracy/sharing of copyrighted content. They are not a group that is for the PS3 Scene, they just enable piracy. Same as PC/BD/DVD/TV/etc. scene groups. They follow a set of rules that release groups make for a scene, and release things for downloading.
How long will they keep releasing 3.55 fixes? Who knows. Their goal is to release something that is working. They may just drop 3.55 or may release Eboots/games that work on all custom firmwares.