New Form 1065 K-1 split box 4

I note box 4 is split on the 2019 Schedule K-1 into a, b & c

are both a & b self-employment income?

(Don't have a completed k-1, just have a question asked me about it that I can't answer and just wondering how it will work.)

thanks 

I believe so. See Treas. reg. 1.1402(a)-1(b) re "use of capital" payments.