I have a similar issue. However, I get a critical diagnostic in Lacerte trying to file 2553 with Late Election. The diagnostic indicates that I cannot file an election with the return of the start date of the entity is less that one from election. 
So the entity was formed 6/18/21 and we want the late election to start on that date. Lacerte is not agreeing with me. BTW, the client mailed in the 2553 and Late Election 3/18/22. I  have my fingers crossed that they have processed it.  If not, what are my options/work arounds for getting Lacerte to take the 2553 with late election on 2021 being a short year?

Thank you in advance for reading my question and hopefully helping me find a solution.

Brian