2023 Schedule K-1 has Box 16 checked but I did not recieve a K-3
My 2023 schedule k-1 has box 16 checked for a K-3, but not form k-3 was attached, and the company I received it from does not expect it to be ready until the summer. Do I need the K-3 to file and need to file for an extension, or can I file now?