Massive Entertainment's launch of The Division 2 went much better than the launch of the first raid, Dark Hours, which prompted them to reevaluate priorities for the second one. As a result, it has been pushed back to 2020 release.
The Division 2 developers are looking to make the game's second raid fulfil the expectations of both them and the players apparently. This seems to be a direct result of the push back they received from the first raid's release, which turned out to be a polarising feature.
Many players who found the challenge to be refreshing for The Division franchise praised it but many also found the lack of matchmaking for Dark Hours equally egregious as it has no easy mode. Considering raids are supposed to be the most difficult content, having the latter would defeat the purpose. Massive Entertainment eventually budged on both fronts and indulged the player base.
Now it appears that they want to avoid these troubles altogether with the next raid. It was supposed to be released in late 2019 originally but Ubisoft released an announcement stating they want the raid to meet both their standards and those of the players.
It is possible at this point that the raid will come with the story mode and matchmaking from get-go but players will have to wait a few more months to get it.
Until then, the players can enjoy bullet sponges in various other activities, possibly including the new Pentagon missions that are coming with Episode 2. Keep in mind that Technician is coming in the same update so get ready for the Special Field Research in case you don't have the Season Pass.