NSA configuration in Stage3

Hi,

After looking at this links, I understand that eNB (S1 interface) is not available at all in Stage3, and it is completely standalone (gNB (NGAP)).

If the above understanding is correct, is it possible to have Stage3 (SA(gNB)) and Stage1 (NSA(eNB)) coexist in one machine?

If I’m wrong, is there any way to enable eNB(S1) on Stage3?

Thanks