I agree, these meds work best by building up a constant level in your body. Yo-yoing can do horrible things to how you feel.
Some people maintain themselves and stay well on just a very low dose. I would also recommend taking the 50 mg until you see your doctor. When more settled, you should be able to wean down again like you did before.
I'm very slow weaning off some antidepressants, and might even need to use half the smallest tablets of this one at the end of the process, rather than whole ones with this med. Sometimes doctors are a little optimistic about how long the process takes.

Good luck and hang on in there. You did it before, so can do it again.