Tile integration last timestamp appears to have some timezone handling issues

[brilthor]

The problem

The last_timestamp attribute on the device tracker appears to be off by 8 hours when I compare the location history in the tile app with the value presented in home assistant properties. I'm not sure where this particular offset is coming from since the HASS server runs in UTC-4 / -5

The app shows 9:16AM and the HASS value is 2023-12-18T17:16:25.001000

What version of Home Assistant Core has the issue?

core-2023.12.0

What was the last working version of Home Assistant Core?

No response

What type of installation are you running?

Docker

Integration causing the issue

Tile

Link to integration documentation on our website

https://www.home-assistant.io/integrations/tile

Diagnostics information

config_entry-tile-f8b5260b28aaa80942b705a0420c6769.json.txt

Example YAML snippet

No response

Anything in the logs that might be useful for us?

No response

Additional information

No response

[home-assistant]

Hey there @bachya, mind taking a look at this issue as it has been labeled with an integration (tile) you are listed as a code owner for? Thanks!

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[bachya]

We merely show the data that we receive from the app. We assume this timestamp to be in UTC, which is what we pass to HASS. I don't have any immediate ideas on why your system is showing a different time.

[SpaceSaver]

For me the last_timestamp attribute shows UTC time as local time. So, if it's 3PM UTC it will show the time as 3PM in the attribute even though it's 10AM EST.