It could be your Twitter settings for time zone has been changed? Perhaps your using some type of Twitter API program that requires your settings and uses a different time zone that is not is sync with your account settings and has changed it?
Check your Twitter Time Zone here:
https://twitter.com/settings/account
For different Time Zone settings changed within my Twitter account. You must click the save button and enter your twitter password to confirm.
http://twitter.com/settings/account
It looks like your twitter page is getting tweets from a specific server in a different time zone location. Perhaps your router is not configured for Daylight Savings Time and is getting some type of time reference from there? Those are the only two guesses I have.
Check your local computer time here:
https://time.is
One last thing is browser plugin which changes time zone settings for privacy, such as Change Timezone (Time Shift) for Google Chrome. Other than that, I would close all pinned and open twitter tabs and CLEAR those cookies out, as your cookies might be corrupt. Cheers anon!
On my Twitter home page I see an offer to opt-in to the NEW TWITTER which is what they might force you to use when not logged in? Just in case, delete your Twitter cookies often in case they break.
New Twitter Coming Soon
I tested the new twitter and did not like it. It is probably full of glitches and whatnot. Anyway, I switched back to Legacy Mode until their beta interface is ready deemed ready for the masses.
Excellent example how Fake News obeys their 4 AM talking points.
Blaming any future global Twitter issue on the "new" interface is an excuse waiting to happen.
Close all Twitter tabs and pages. Clear all of your Twitter cookies and revisit the page to see if the problem goes away.
New Twitter is coming soon, so this could be a bug.
Do a web search for What Is My Location. Google Chrome will show your device on a map. Other search engines will offer tools that do the same thing. If your revealed location match the timestamp in those tweets, then that could be why it's only affecting you.