IOS app not switching from Internal URL to External URL when iphone goes out of home wifi range and switch to cellular mode

iOS device model, version and app version
Model Name: iPhone 12 Pro Max ( Tested with another iPhone 13 too )
Software Version: ios 18.3.1
App version: 2025.2 (2025.1177)

Home Assistant Core Version
2025.3.1
Supervisor
2025.03.2
Operating System
14.2
User Interface
20250306.0

Describe the bug
IOS companion looses connectivity when the Iphone goes out of wifi range and auto switch to cellular mode.
Connection status in server settings stay on "Internal URL" instead of switching to "External URL" and the companion stay endlessly offline.

1 - To get the connection again i need to kill / restard the IOS companion, or manualy "clear frontend cache", or switch airplane mode ON / OFF on the iPhone

2 - IF I m on my home wifi connection and i switch off the wifi on the iphone,
IOS companion switch immediatly as expected on external URL
IF i connect again on my home wifi,
IOS companion switch immediatly as expected on internal URL.

3 - The problem occurs when i m at home connected with "Internal URL" and i go out of home wifi range ( leaving home ... )

To Reproduce.
Being connected with internal URL on home wifi
then
walk away from home wifi signal until Iphone switch to cellular

Additionnal info
External URL is working and setuped with nabu casa.
Home wifi name is setuped in internal server settings.
All authorisation are granted on ios device.
Position : always
Exact position
Bluetooth
Local network
Background updates
Cellular