At this point I haven't logged into the game yet or downloaded the patch but I wanted to give some info based on my experience with this mission.
#1) The 20 hour cooldown timer doesn't start until AFTER you talk to the contact and claim the reward. About a week ago I hit tier 2 and tried this mission when I found it bugged. I dropped the mission and was able to take it again right away. Did this until I managed to complete the mission after the 3rd try.
#2) Someone posted a workaround somewhere on the forums that seemed to work for me. When you first enter the mission your mission says something like "investigate the cave" or something. At the end of the tunnel where you spawn at the entrance of the mission, a group of Tal Shiar spawn and start coming toward you. At the end of this tunnel when you get there your mission updates to clear out the Tal Shiar. (After the tunnel is a large open area that has a group of enemies near consoles to click on and the first prisoner)
The workaround: As soon as you enter the mission run straight to the end of the tunnel and don't kill any enemies until you hit the trigger that updates your mission objective. Even with bridge officers not set to passive you should be able to get past the first group to hit the objective update. When I did this the last time I met the enemies right at the ened of the tunnel and triggered it just after I came into contact with them. (Press the Shift key -by default- to make your character run faster for those who may not know) *Note: this may not work for everybody*
What they need to do is either place the location of the "trigger" that updates your objective closer to your spawn in point at the mission entrance, add it to the first group of enemies to where it updates your mission as soon as you come into contact with them, or just remove the first objective to "investigate" or whatever it is and have your first objective be to defeat the Tal Shiar.
I use to be with it. But I don't remember what "it" was. Now what I'm with isn't it, and what's it seems weird and scary to me.