How to build the same toolchain but with a different GCC version?

Hi,

I know it's possible to reproduce a build as per the instructions in the `README.txt` file. However, I want the toolchain to contain a slightly different GCC version.

For example, I want to build the toolchain `aarch64--glibc--stable-2020.08-1`, but it should contain GCC 9.4.0 instead of GCC 9.3.0. How can I achieve that?

Thanks!