The purchase agreement list's the seller's name as sole shareholder + his SCorp (Professional Corporation). 

My initial thought was try to get the 2024 1120S return done before 10/15 and file it late to allow the K-1 to flow to 1040. Not sure if this is doable on my end + client would incur $220/month penalty. Doing this preserves the $345k basis correct? Or can the basis be carried over to the 1040 without filing a 1120S?

Wondering if the 7203 filed with the 2023 1040 can be used to support this basis.