Initial Starter Amount and Scaling For Future Needs

[BCS430]

Im about to develop my SD starter and Im sure Craig's model is probably the best way to initially determine the amount of SD starter I will need for my current recipe, fermentation times, etc.

However, once my starter is mature, is there a formula/ratio that will allow me to scale/grow it without starting all over with a larger initial starting amount?

Let's say I eventually need to double the amount of starter,  can I just feed more and discard less during the feeding process?  Is there a min/max ratio for feeding to grow it?

[parallei]

Let's say I eventually need to double the amount of starter,  can I just feed more and discard less during the feeding process?

That is what I've done and my starter has been happy for years.

Is there a min/max ratio for feeding to grow it?

I'm simple minded, so when increasing the starter amount (say to double it to give half to a friend) I've just always used the same ratio I always feed at.  In my case that has always been: 2 parts starter, 1 part water, 1 part flour (100% hydration).  So if I have 150g of starter at 100% hydration, I don't discard any and add 75g water and 75g of flour.  Now I'd have 300g of starter at 100% hydration.