Moreover, FR24 data is not synchronous, it's subject to whatever latency exists in the Internet connection between the enthusiast's receiver and the server.
That's particularly apparent in this instance, where the published data comes from 3 separate receivers, presumably in 3 different locations (see column 13 in the CSV file). Those clearly aren't time-synchronised, which is why we see wild variations of parameter values within the same second.
In other words, trying to construct a time-series with the data is fraught with problems. I'm very disappointed that ASN appears to have fallen into that trap with their dodgy graph.
But the time on the data is that added when it was transmitted, not when it was received or sent by the server.
COAA also calculate position by triangulation when they do have the positionless data fromby the aircraft but I am fairly sure it is still timecoded. People using that method have to have their computers synchronised to a time standard and it is rejected if their PC clock is not correct.
I have supplied ship's AIS data to the authorities a few times, it has similarities to that from aircraft and can be used by them to reconstruct what happened.