I just typed a long post and lost it!

Okay, well, here goes.

Using teaching blocks of time really helps me balance my time nicely among my dc. With the guides you are doing, it could look something like this...
Teaching block with 9 yo (work up to 45 minutes)
6 yo plays with 2 yo and 4 yo
Teaching block with 2 and 4 yo, half-speed LHTH (15-20 minutes)
6 yo does independent Beyond activity (poetry copywork)
9 yo does independent PHFHG activity
Teaching block with 6 yo, do half of Beyond (work up to 45 minutes)
9 yo does independent PHFHG
2 and 4 yo watch an educational video away from other dc or do something independent off your list
Teaching block with 9 yo (30 minutes or so)
2, 4, 6 yo have snack and listen to book on tape, color, puzzles, something off your list
Teaching block with 6 yo to finish Beyond (45 minutes)
9 yo plays with 2 and 4 yo
Oversee 9 yo finishing out PHFHG
6 yo plays with 2 and 4 yo or all do something off list
Here is a copy of our schedule back when we did PHFHG and LHFHG, in case it is helpful...
Here is a copy of our schedule from last year, doing RTR, half-speed Bigger, and half-speed LHTH...
I hope something here can help, but in general, the 5 best tips I have for teaching multiple guides are to have a set start time each day, to plan for the littles, to use teaching blocks of time, to have your olders learn to play well with your littles, and to use the same routine each day so dc know what is expected.

Keep asking questions until you are set, but in my experience teaching multiple guides is not hard to do with some planning ahead and a good routine! HTH!
In Christ,
Julie