Originally Posted by
Nuse
You are, if you change your base permanently. The way it works is you change your base to clan war base right before the preparation day ends. You can see the exact timer and when that timer hits 0 the base you have at that time will be the base you have in that specific war.
Change your base to clan war base right before timer ends then change it back to your normal base once preparation day turns into war day. I.e you will only have to have the war base for a very short amount of time if you do it right.