I've been trying to get an answer to this question on other forums (the folks at SuperUser thought this was the place I needed to post) and via my connections, but I haven't gotten very far. Hopefully you guys can help me find an answer:

I've got a dozen old subdomains that have been indexed by Google. These have been indexed as both http AND https.

I've managed to redirect all the subdomains properly, provided they are not https, but can't get any of the https subdomains to property redirect.

Here's the code I'm using:

RewriteCond %{HTTP_HOST} ^subdomain1.mysite.com$ [NC]
RewriteRule ^(.*)$ http://www.mysite.com/$1 [R=301,L]

RewriteCond %{HTTP_HOST} ^subdomain2.mysite.com$ [NC]
RewriteRule ^(.*)$ http://www.mysite.com/$1 [R=301,L]

RewriteCond %{HTTP_HOST} ^subdomain3.mysite.com$ [NC]
RewriteRule ^(.*)$ http://www.mysite.com/$1 [R=301,L]

This works great until someone goes to:

https://subdomain2.mysite.com$ 
which is not redirected back to http://www.mysite.com$

How can I get this to work? Additionally, I'm guessing there is an easier way to make it happen than setting up a dozen pairs of Rewrite conditions/rewrite rule? Is there any way to do this in just a few lines, including one where I list all the subdomains?

I'd actually also like to redirect everything on https://www.mysite.com$ to http://www.mysite.com$ except for 3 folders

These are mysite.com/secure, mysite.com/store, mysite.com/user --> is there any good way to add this to the htaccess file?

Any suggestions would be great! Thank you in advance for any help.