You've found it Микола Корнієнко!
After intensive testing I can confirm that the tagging is the problem. To be specific: when you add a new tag and press enter, the Date Created field is cleared and becomes empty. Thus the date stored is not correct.

I've tested it on K2 v2.8 as well. Here the bug doesn't occur.
The difference is that the (date) publishing and meta fields are not in a sidebar, but in a tab (like the admin interface in v2.7).

Be aware: if you've created your own K2 template (override), you must update this to v2.8, otherwise the new-article form in the frontend becomes a mess and you're not able to write and save new articles.
I want to do some more testing with v2.8 to make sure no other issues are there, before I install it on my live site.

I would like to encourage the developers of K2 to release a stable v2.8 a.s.a.p.

Dev v.2.8.0 did it for me. Thanks.

Steven Trooster wrote: You've found it Микола Корнієнко!
After intensive testing I can confirm that the tagging is the problem. To be specific: when you add a new tag and press enter, the Date Created field is cleared and becomes empty. Thus the date stored is not correct.

I've tested it on K2 v2.8 as well. Here the bug doesn't occur.
The difference is that the (date) publishing and meta fields are not in a sidebar, but in a tab (like the admin interface in v2.7).

Be aware: if you've created your own K2 template (override), you must update this to v2.8, otherwise the new-article form in the frontend becomes a mess and you're not able to write and save new articles.
I want to do some more testing with v2.8 to make sure no other issues are there, before I install it on my live site.

I would like to encourage the developers of K2 to release a stable v2.8 a.s.a.p.

How do I update? I do not understand. Here are my overrides. Thank you

Google Drive

K2 2.8 will be ready within the coming days.
You can use the DEV version located here: github.com/getk2/k2 click on the green button in order to download the extension.

Микола Корнієнко wrote: How do I update? I do not understand. Here are my overrides. Thank you

Read my post about updating here:
www.joomlaworks.net/forum/k2-en/47780-error-double-timezone-specification?start=10#162860

Yes, this does need to be addressed. It has been happening to me, but by reading this forum I have learned to make a change to the "Creation date" found under Publishing & Metadata, although it seems to revert back at some point. So it is something the team will need to look at.

Thanks!

Is there a fix for the version 2.7.1 to apply? The fix from Reaction didn't worked for me and I'am currently not able to do a full update of K2.

Krikor wrote: K2 2.8 will be ready within the coming days.

Again we are not seeing any progress in the development of K2. Everyone who cares about updating to the newest Joomla version should experience the same problem. I don't want to update to any GitHub-Dev-Version of K2. What is the exact fix for this problem?

Just wondering if there is an estimated release date for a stable v2.8 of K2 as it has now been two weeks since the last message saying it will be ready in the coming days. Our client is experiencing this issue but would prefer to use the final stable release rather than using a possibly unstable dev version.

Thanks

Within the coming days, a last issue is being tackled (modals) and 2.8 will be ready or the DEV will be 100% safe.