Question about BMR

Mommagoose4

So I have read people saying you should always eat close to your BMR - So MFP says thats 1716 a day - yet they allot me 1320 calories. I do exercise - I try to burn about 500 - 1000 but its usually over 1000. I have 4 kids - SAHM - lightly active status.
I am 5'6" & currently 217-218lbs.

I see a dietician in a couple weeks but don't want the next couple of weeks to go by without progress. I seem to be at a plateau.
Anyone who wants to add me as a friend to check out my diary may - I have been eating 1320 or more & over 100 protein & keeping everything in the good range.
Thank you in advance.