Remove Remove Sub intro post text

Hi

I posted about this problem in a previous post https://premium.wpmudev.org/forums/topic/blogs-mu-remove-sub-intro-post-text

"I managed to get rid of the text on the home page, and the background to it, by deleting the whole first section from the sections.php file, but can't get rid of it on the inside pages. I don't want it anywhere, it doesn't display properly when I try to add text to it, and the fact that you can't delete it is just annoying!"

I have just upgraded the theme, and of course, the sub intro post text has returned. Is there a way I can remove this text from all pages without it coming back at upgrade? I thought a child theme entry would work, but a post in the thread listed above suggests it might not work. This is a part of the theme that simply isn't required for what I need, so I want a way to remove it completely.

Thanks