Katie,
If you have a good strong starter, and if you use/refresh it more
than once a month, it really shouldn't take so long to have it ready
for baking.
I take mine (I keep about half a cup in a small glass jar) out of the
fridge first thing in the morning, put a dollop of starter into a
large measuring cup, add flour and water to create the hydration I
want for whatever I'm baking, and also add flour and water to the jar
with the starter. I set both containers, covered, in a warm spot, to work.
After a few hours I check to be sure that both containers are
beginning to bubble up. put the jar with the reserve starter back
into the fridge, and add enough more flour/water to the starter in
the large measuring cup to bring it up to the amount I'll eventually
need for my recipe.
It's ready to go early in the afternoon, giving me time to get bread
baked before bedtime.
Hope that helps,
irene in hot and dry WA