last_ping is no longer null for a screen that has never connected

A screen’s last_ping used to be null until the screen first checked in, which made null a usable signal for “this screen has never connected”. It is now always a timestamp: screens start with theirs set to when the screen was created, and existing screens that never checked in were given their creation time.

This affects last_ping on the v4 screens resource. The field’s type and the response shape are unchanged, only the values.

If this affects you: an integration treating a null last_ping as “never connected” loses that signal. A screen created in the last four hours can also report Online in its status before the device has ever reached us, because the seeded timestamp is recent. The closest check is comparing last_ping with the screen’s created_at: a screen that has never checked in still carries the timestamp it was created with.