BuddyPress.org

You can try by adding “DirectoryIndex” by way of modifying the HTACCESS file.

The way I did it was I added the line:

DirectoryIndex my-main-landing-page-on-my-home-page.html

this tells your webserver to use that file as the main “index” instead of the “index.php”

it seems to work well as “maintenance page” while keeping all of the functionality of buddypress intact (blogs, members, sign ins, etc) still seem to function.