i think is better talk about UTC time as it is always same everywhere and not change for solar/legal timing like in certain EU country..
you can check the UTC time easily on the net.
however i've noticed that these days some domains expire at very strange timing, also many hours before the usual date..
just an example:
some days ago i was checking some .co.uk names.
that extension start to expire at 20.00 UTC
that days many domains were already free at 18.00 UTC
i'm so tired about those strange changes..
i've noticed that strange expirations also for .be names and .eu ones.
Once we start talking about other extensions then you're going to find allot of "strange" things. Firstly, most extensions drop at different times during the day so you probably won't find .co.uk and .eu domains dropping at the same time. Secondly, once again, it always comes down to how many names are set to drop in that extension each day. There are always hundreds of thousands of COM/NET domains so that drop time frame always lasts a good hr and then some. On the other hand, there may only be hundreds of .IN or other ccTLD extensions dropping in a day so the drop period for that extension may only last 15 minutes or so.
Thirdly, you have to remember that although COM and NET are Verisign extensions, .FR - .CO.UK - .DE - .BE and these other ccTLDs are not. Therefor, their process may not work exactly like the Verisign process does. Some extensions drop their domains throughout multiple hours of the day.. Some extensions also change with Daylight savings time, COM/NET does not.
Finally, are you certain the drop time for .CO.UK domains is 20:00 UTC? The only way one could really find out the exact drop times would be to contact the registry itself (Such as NIC.de for DE domains, NIC.eu for EU domains, afNIC.fr for FR domains, DNS.be for BE domains...etc.) and ask them. Keep in mind, most of them won't tell you - but some might.
I've done allot of research and testing over the past couple years with drop times and they can be pretty tricky. I have times for a variety of extensions but since I don't chase some of them, it makes it even harder to verify..I'll post a few below for everyone to mess around with. As I said, I'm not 100% certain on their accuracy, but feel free to test any and share more input if possible!
ORG domains (Changes with DST) currently:
9:30AM - 10:30AM CST
2:30PM - 3:30PM GMT
UK domains:
4:00PM – 5:30PM CST
9:00PM - 10:30PM GMT
AU domains:
10:05PM – 10:15PM CST
3:05AM - 3:15AM GMT
BE domains:
1:00AM – 1:15PM CST
6:00AM - 6:15PM GMT
EU domains:
12:00PM – 12:15PM CST
5:00PM - 5:15PM GMT
ME domains:
8:30PM – 9:00PM CST
1:30AM - 2:00AM GMT
US domains:
12:00PM – 12:45PM CST
5:00PM - 5:45PM GMT