Gzip requested yet folder show cached php

I am using Wp supercache Version 1.5.5

My .htaccess requests :
RewriteCond %{HTTP:Accept-Encoding} gzip
RewriteCond %{HTTPS} on
RewriteCond %{DOCUMENT_ROOT}/var/sites/s/synergy-health.co.uk/public_html/wp-content/cache/supercache/%{SERVER_NAME}/$1/index-https.html.gz -f
RewriteRule ^(.*) “/var/sites/s/synergy-health.co.uk/public_html/wp-content/cache/supercache/%{SERVER_NAME}/$1/index-https.html.gz” [L]

Yet no index-https.html.gz exists for my woocommerce shop files – instead I have 4 php files:
wp-cache-c6036c1112b78d2dbbec461b425857f3.php
meta-wp-cache-c6036c1112b78d2dbbec461b425857f3.php
wp-cache-ffc868816235a9abf743a7df68f74080.php
meta-wp-cache-ffc868816235a9abf743a7df68f74080.php

Is this due to caching HTTP headers with page content?

Another problem I have is with Preload and refresh – when the refresh interval is reached my entire product cache folders are emptied even though the preload rebuild is set for 40 products. I assumed that a rebuild of 2 hrs and preload of 40 pages would mean a slow cache rebuild of 40 pages every 2 hrs. Have I got this wrong?

Thanks
Steve