RDT - First of all, Welcome to the forum
There are lots of ladies on here who are transitioning (myself included). My tips are reduce brushing and combing. With the two textures on your head, you are bound to get some minimal breakage, esp if you are combing and brushing everyday. The key to managing that is moisture, moisture, moisture and low manipulation.
I condition was every other day when it is warm enough to and in the summer I CW every day. I only detangle once a week after deep conditioning with a wide tooth comb like a Mebco or K-cutter. The rest of the time I finger comb to detangle in the shower. Use a good moisturizer and seal with a light oil.
Use protective styling when you can - buns, phonie ponies, wigs. Or better yet, if you can cornrow your hair, that will allow you to leave your hair alone for days at a time.
You say your hair is currently BSL. What length would it be if you BC'd now ? Long enough to pull into a ponytail? When do you plan to BC? Or are you waiting for your natural hair to grow out to BSL too?