Guess what ... BLOCK will not support older systems either for long ... they may for one more year but it is also their SOP to drop old OS. They may still support 10.13 for 2020 but probably will not for 2021 ... they have done this on purpose to grab TT customers looking to jump ship then they also stop supporting old OS after a year or two ... just want to make you understand what will eventually happen.
If you cannot upgrade the OS or will not buy a new computer you can continue using the TT Online version to preserve the chain of info but do what you want.
