Let the clock turn over to the next day. The real cost should show up. As to why the ai is build 10 lines of subs???? Who knows lol. Are they low on manpower?
It's 18 lines, not 10. I ran it for a day to see if it changes.

2 show up August 8, 1941.
1 shows up November 22, 1941
1 shows up December 15, 1941
2 show up January 3, 1942.
12 show up February 22, 1942.
The Submarines also have torpedo tubes and for some reason, they are only allowed improved hull.

My guess is the AI gets a script and it is similar to when you start the game and a bunch of very low cost builds are in the queue. So Germany is scripted to build lots of U-Boats.
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