I've observed that when Holiday Mode is activated, all sub-accounts automatically adjust to provide currency relevant to my current location, despite the toggle being located under individual sub-account settings. To clarify, activating Holiday Mode in the settings of a specific sub-account should only enable it for that sub-account, not all of them.
A scenario for context: Suppose I am currently in location X and, prior to my trip, I created a sub-account specifically for all purchases linked to this trip. Alternatively, I might have changed my card settings to be mapped with a sub-account, allowing me to easily track all expenses incurred during the specific trip. In such cases, I would expect only the designated sub-account to reflect the Holiday Mode's currency adjustments, not all sub-accounts.