As we deploy 2019 AutoCAD, I'm wanting to automate the default save format to AutoCAD 2013 until everyone is upgraded, then switch it back to AutoCAD 2018. We have a pointer in our acad2019doc.lsp that looks to our main lisp file on the network, it has our custom tools built into it. Everything in there works fine, except the format save will not work. Any ideas out there on what the reason might be?

(setenv "DefaultFormatForSave" "60")

Thanks!