Changing Publication date does not re-order my posts.

Latest post by date shows up first. If you want an older post to show up first, you have to reverse the date order, which can be as simple as changing the time of publication. For example I have photography lessons on my site, and I wated them to post in order but of course the last lesson I wrote shows up first so I reversed the pub dates using the clock.

last post lesson 7 published at 12:00noon lesson six at 12:01 etc. 

In your case first post would need to be 10/02 second post 10/01, third post 9/30 etc. The first one shows up at the top of the blog page, then second then third. 

FYI, if using a blog summary block changing the original blog post pub date reorders the summary items as well. 

Look at my page, the first item to show up was the first one published. I changed the pub date to make it the last one published to make that happen. 

https://myrandomviews.com/stories/lessons