Unlikely timestamp from Phoscon APP 'Events' tab

Hello,
I’m trying to figure out if my PHP websocket client based on GitHub - sirn-se/websocket-php: [php-lib] WebSocket client and server in PHP is responsive, and while analyzing some results, I came across this inconsistency.
I’m using deCONZ websocket with websocketnotifyall = false; it’s very efficient.
I’m comparing the responsiveness with Phoscon APP on Windows, ‘Help’ menu, ‘Event’ tab.
I get this:

“10:54:53:56”: {
“e”: “changed”,
“id”: “186”,
“r”: “sensors”,
“state”: {
“humidity”: 6620,
“lastupdated”: “2025-10-07T08:54:54.946”
},
“t”: “event”,
“uniqueid”: “f4:b3:b1:ff:fe:4e:d3:b5-01-0405”
},

My PHP websocket client is reporting 54:54.947, which is very fast.
But how is it possible that an event updated at 54:54.946 can be reported at 54:53:56 in Phoscon APP ‘Events’?
I can find quite a few similar cases.