Local mirror as way to mitigate bug #718225

[dbgr]

Hello.

I am using the live-build version 20191221 (the one in testing) on a 
debian stable/buster system to build an live image with and integrated 
debian installer cdrom (with the '--debian-installer live' flag/option) 
with no problems, but I stumbled upon this bug -> 
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=718225 and was 
wondering if setting a local mirror would suffice to mitigate it...

If it is, can anyone guided me in the process of setting the 
aforementioned mirror? Which files should I download and made available 
and how? And how I could made live-build aware of the mirror and 
download the files it need correctly?

Thank you.