Hi Anthony,
Here are what have been left:
root@voyage:~# ls -la /var/lib/apt/lists/|wc -l
40
root@voyage:~# ls -la /var/cache/apt/
total 43372
drwxr-xr-x 4 root root 74 Dec 1 03:49 .
drwxr-xr-x 9 root root 60 Dec 1 04:45 ..
drwxr-xr-x 4 root root 30 Dec 1 03:48 archives
-rw-r--r-- 1 root root 22216528 Dec 1 03:49 pkgcache.bin
-rw-r--r-- 1 root root 22195993 Dec 1 03:49 srcpkgcache.bin
root@voyage:~# du -sk /var/cache/apt/ /var/lib/apt/lists/
43372 /var/cache/apt/
89389 /var/lib/apt/lists/
I would expect if "lb chroot_archives chroot remove" works correctly, at lease the above indices should not exists in the final live-image when LB_APT_INDICES=false.