You must look at this whole mess like this, StrikeRaid: SoulWorker seems to have a very low priority for GF, so only a few people (maybe you can count them with one hand) work at this project. The upper management only wants to see numbers, so they milk the game like they did with other games.
I lost any hope that they will change their course and only wait for the shut down notification.
I can imagine that the Chii Advancement or DH part 2 will be announced at the end of march at the earliest. With some luck, we will get one of them than. GF did this for some while in Aion, too. They only react in the last possible point in time, but we even transgressed/crossed this point.