Why can't I begin assault?

[MasterOfPuppies]

http://i.imgur.com/5VJqio8.png

[Rhonda]

It helped me a lot to learn, that you can assign multiple units to the same location.
Read the reports carefuly, some locations are better not used (e.g. diver drowning)

[MasterOfPuppies]

I even tried this guide: http://steamcommunity.com/sharedfiles/filedetails/?id=741486931

But it doesn't work. I still can't begin the assault. Also I'm missing some units. For example, I don't have any "Water Assaulter"

[Rhonda]

You might need to play further until the option is unlocked. IIRC you can only attack on the last day.

[MasterOfPuppies]

I'm at the end of day 178.