Wordpress Cloudflare Polish issues

So I've enabled CF Polish on one of my test subdomains and noticed that Polish wasn't doing it's thing.
After digging around the cmm nginx config files I noticed that all images had the "no-transform" header (in addition to the Vary "accept" header).
Further digging narrowed this down to wpsecure_mydomain.com.conf

I made a couple of tweaks as follows:
- commenting out the no-transform and Vary "Accept" headers
- adding gif to the image list
- extending the expires to 365d (to keep Google Pagespeed Insights happy)

Code:

# WebP extension support if you are converting /uploads images to webp
location ~ ^/wp-content/uploads/ {
  #pagespeed off;
  #pagespeed unplugged;
  #autoindex on;
  #add_header X-Robots-Tag "noindex, nofollow";
  location ~* ^/wp-content/uploads/(.+/)?(.+)\.(gif|png|jpe?g)$ {
    expires 365d;
    #add_header Vary "Accept";
    #add_header Cache-Control "public, no-transform";
    add_header Cache-Control "public";
    try_files $uri$webp_extension $uri =404;
  }
}

CMM version:
123.09beta01.b616

With my tweaks above, webp's are being generated where relevant (and smaller than the original source).

I'm guessing I shouldn't need to do this?
I know CF doesn't support vary and you've got code in place that detects CF - but does that also impact a pro account as per above?

 

In my scenario I didn't *think* I had enabled webp serving! How do I disable it and I'll check if I had enabled it at some point.