Different owners, different schedules
The phone maker maintains firmware while each app developer chooses supported OS versions. Their timelines can diverge.
Working is not patched
An unsupported phone may still run apps, and a supported phone may lose one app. Neither condition proves the other layer is healthy.
Check the full chain
For important services, check device support, patch level, OS compatibility, app notes, and the provider's minimum requirements.
Primary sources
Important
Device support and safety information can change. Recheck the linked manufacturer and regulator evidence before making a purchase or safety decision.