I have a similar setup.
Basically, rules are tied to interfaces. And interfaces are virtual based on VLANs. So, if you won't remove VLANs, rules should be fine too. You just need to:
remove igb6, igb7 from the lagg
create lagg1
add igb6, igb7 to lagg1
reassign interface on vlan10 from lagg0 to lagg1
Done. All rules should be untouched. No reboots, not even a downtime.
But certainly perform a config backup prior to changes.