GaryS

Since Sweetgum has alternate leaf nodes I would treat it like a Hornbeam rather than like a maple.
It will bud again when pinched at the four bud or the 2 bud.
Don't let the internodes get too long, this can happen when you let it go to the four bud length but you can always prune that back more.
It's kind of like a hornbeam and kind of like a maple....2, 2, two trees in one.

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GaryS