8 and 9 syncs are different. 8 still uses pungi and we direct non-stable
composes to /mnt/compose/8-.../ instead of changing the profile to
accomodate. All 9 release will sit in /mnt/compose/9 and same with
future major versions.
All SIG's sync to /mnt/compose/MAJOR. There are no plans for SIG's to
sync to non-stable.