If you want the R2019 startup spalshscreen you will have to purchase that license and abandon LT2019.

Or disable the startup splsshscreen altogether (for Windows, not sure about the MAC, that is a separate forum) https://cadpanacea.com/wp/?p=54

MAC forum is way over here https://forums.autodesk.com/t5/autocad-for-mac/ct-p/4051