My advise is,
Use manual fcs at all CAs and all BBs only. Using manual at lower level ships with that
bad spread you just make your life harder.
I learned manual on my first BB1 and it wasn't hard at all.
Generally speaking you can't see the manual difference in blitz because of the low level
gunner's bad spread (with exception of close hitting).

Learning to use AA helps to learn manual alot. and fairly easily.

The spread of your shells will be much wider, and your range shorter, then with
manual. And you get a reduction to your experiance if you use auto.
99% of all BB players use manual, it is basically the only way to go if you want to
have a chance.

Auto fcs in BB4~ is not advisable, ~BB3 depends on the nation what you use. And
learning manual fcs in BB1 isn`t that hard
actually, because I could do it.

Manual requires an adjustment period. It is highly advisable that from DD and even CL that you started learning
Manual. Using Auto FCS on a BB1+ is *NOT* advisable.