ArenaNet didn't release a new strike mission with the first chapter of Champions but they did mention more are planned for future Guild Wars 2 content.
Guild Wars 2: The Icebrood Saga is currently in the first stages of its four-part finale named Champions. This first stage, Truce, appears to have not lived up to the expectations of a fairly large chunk of the community, one of the reasons being their dissatisfaction with Dragon Response Missions which debuted instead of a new Strike Mission popping up.
That said, not all players preferred Strikes over DRMs but the sentiment is there. It is this portion of the player base that will be happy to hear that more Strikes are indeed coming in the future Guild Wars 2 releases and the appearance of Dragon Response missions does not mean Strikes were discontinued.
This info is coming from ArenaNet developers themselves, who noted that they have plans to release more Strikes in the future during a preview event for Champions - Truce. One of the driving factors to make more Strikes seems to be the positive reception they had from the player base.
However, the devs couldn't provide more info on the future missions and that means to ETA is around. We are still early into the Truce chapter though and the next one is slated for January 2021.
Strikes are not the only content that resonated with the players though as the reception of Sunqua Peak fractal was pretty good along with the global event that ran its course for charity recently.