Found a solution:
in the funtions.php file I added another stylesheet rule like this:
if(is_home() )
$stylesheet_uri = $stylesheet_dir_uri . '/stylesheet_name.css';
The reading setting makes your posts page a 'home' page. Luckily this has not affected my actual home page (the drop down otion above in the reading settings panel). My home page has another stylesheet applied to it.
For anyone wanting to see my exact function snippet to apply different stylesheets, here it is:
// PAGES CSS
add_filter( 'stylesheet_uri', 'my_stylesheet', 10, 2 );
function my_stylesheet( $stylesheet_uri, $stylesheet_dir_uri ) {
if(is_home() )
$stylesheet_uri = $stylesheet_dir_uri . '/style-about.css';
if ( is_page( 'team-building' ) )
$stylesheet_uri = $stylesheet_dir_uri . '/teambuild.css';
if ( is_page( 'the-canape-challenge' ) )
$stylesheet_uri = $stylesheet_dir_uri . '/teambuild_cat.css';
elseif ( is_page( 'Contact form' ) )
$stylesheet_uri = $stylesheet_dir_uri . '/form.css';
return $stylesheet_uri;
}