Hummingbird GZIP Disabled for text/html

Checked with my host and ran the following command:

$ curl -I -H 'Accept-Encoding: gzip,deflate' -L http://usarugby.org/readme.html
HTTP/1.1 200 OK
Date: Wed, 27 Apr 2016 19:04:02 GMT
Server: Apache
Last-Modified: Tue, 26 Apr 2016 21:11:27 GMT
ETag: "1cc0-53169bc7b00e6-gzip"
Accept-Ranges: bytes
Vary: Accept-Encoding,User-Agent
Content-Encoding: gzip
Cache-Control: max-age=0
Expires: Wed, 27 Apr 2016 19:04:02 GMT
Content-Length: 2980
Content-Type: text/html

However, Hummingbird says that GZIP for text/html is disabled. It's the only performance-based plugin I have enabled at the moment.

Any ideas?