When I started Bavaria, the place came with 12 ships- two Ausberg class flotilla leaders and 10 T1 class Torpedo boats.

The Ausbergs are up for overhaul, the T1s are close, and all of them have old gear in need of updating, and I needed a SS to figure out what various changes would 'work' and cost.

So I put their stats into SS and found that they use 1906 and 1907 engine years respectively, which is not actually an allowed engine year. The designs fail when changed to the appropriate 1905 engine year.

So....what is the 'correct' course of action?
Do I get to keep the off-date engine years, basically ignoring them?
OR
Do I have to go back and change the engine year, then alter the design?
 

Since you inherited the problem, I'd say you just leave the off-date engine years as they are.  It's not like they give you a huge tactical advantage now.

It's the reply I expected, but better to ask than just forge ahead.