Head office admins can move an office onto another of your brand packs.
In head office mode, open Offices.
On the office's row, open More actions (⋮) and choose Switch brand pack.
Pick the new brand pack. The current one is greyed out.
Decide about automations. Tick Remove this workspace's existing automations for a clean start: every automation in the office and its run history is deleted, but posts, creatives and campaigns they made are kept. Leave it unticked and the old automations keep running on the old brand.
Click Switch brand pack. Then install the new brand's automations from the office's Automations page (enter the office from the Offices list, or ask the office to do it) and turn them on.
What changes
Logos, colours, fonts, post messages, creative templates and landing page settings.
What doesn't
Posts, creatives and campaigns the office has already made, and the office name, website and email (update those separately).
Tip
Switch on the Brand pack column in Offices to see which pack each office is on.