Bug: Subdomain's "Disable redirection" has no effect...

I know there are some threads on subdomain redirections but none addresses my specific problem.

1- i created a subdomain
2- I never asked for any cpanel redirection nor clicked on "manage redirection"
3- I uploaded a small htaccess to the subdomain's folder (see below)
4- and then cpanel automatically created a redirection code inspired by what was in the htaccess... (duh) but not exactly similar... (see below)
5- it seems to interfere with the behaviour I want the htaccess to have (redirect without changing the url...)
6- I try the "Disable redirection" button but it won't budge... the redirection remains there...

My questions:
1- What the heck? Why does cpanel take it on itself to create a redirect i didn't ask for?
2- is this a bug or something i don't understand? What's the solution?

Here's the code in my small htaccess:
RewriteEngine On
RewriteCond %{HTTP_HOST} ^apps\.mymaindomain\.com$ [NC]
RewriteRule ^list-(.*)-apps-software$ http://www.mymaindomain.com/somephpscript.php?item=$1

And here's the "so-called redirect" cpanel added on its own:
http://www.mymaindomain.com/somephpscript.php?item=

Thanks for any help.