Is this command applicable to supervised devices only? On unsupervised device the command failed with CommandFormatError error. Neither in https://developer.apple.com/documentation/devicemanagement/settingscommand/command/settings/timezone nor in response below it is mentioned that the command is supported on supervised devices only.
Request:
<plist version="1.0">
	<dict>
		<key>CommandUUID</key>
		<string>337531bb-0b5d-4959-aad8-6bb5751bfeed</string>
		<key>Command</key>
		<dict>
			<key>Settings</key>
			<array>
		<dict>
				<key>Item</key>
				<string>TimeZone</string>
				<key>TimeZone</key>
				<string>Europe/Paris</string>
		</dict>
</array>
			<key>RequestType</key>
			<string>Settings</string>
		</dict>
	</dict>
</plist>
Response:
<plist version="1.0">
<dict>
<key>CommandUUID</key>
<string>337531bb-0b5d-4959-aad8-6bb5751bfeed</string>
<key>Settings</key>
<array>
<dict>
<key>Item</key>
<string>TimeZone</string>
<key>Status</key>
<string>CommandFormatError</string>
</dict>
</array>
<key>Status</key>
<string>Acknowledged</string>
<key>UDID</key>
<string>17885e13a0919f1bb24bd4e410e6260552af0afe</string>
</dict>
</plist>
Topic:
Business & Education
SubTopic:
Device Management
Tags: