Inserting a large year value in the date field of the blog post causes unexpected behaviour and/or lost pages.

To replicate this bug, I created a blog post and changed the year to:
190728635190728635190728635190728635190728635-08-11 (A bit ridiculous, but fun )

And then I added some random crap into the required fields and clicked submit.

What happened was one of two things:
1) everything gets created fine, but the year gets changed to something more palatable for Confluence to understand (e.g. 190728635 > January)
2) Everything appears to be created fine, but the blog page itself doesn't get created and you get a "page not found" error
(please see attached images)