How many calories with 30 Day Shred?

Nightfall30

I just started Jillian Michaels' 30 Day Shred, I will be doing Day 3 today. I am not following her diet plan because I like flexibility in terms of food. I have seen some amazing progress pictures for this programme and I am really inspired to finish the 30 days too - however, I am confused about how many calories I should be consuming. I am currently netting about 1300 kcal a day (I calculate over the week and tend to cycle my calories) and eat about 100 g of protein. I am 5'3" and weight ~138 lbs right now, if it helps. My BMR is 1359 kcal and and I maintain around 1900.