All three go to the same address. Say which one it is in the subject line and it gets to the right person faster.

Within two working days, from a person rather than a queue. There is no support tier, so a free reader and a Pro member reach the same inbox.
Please do, and say where you are — first ML role, or moving up a level. If the honest answer is that the free tracks are all you need for now, that is the answer you will get.
Send it. Corrections are welcome and get credited, and a mistake in the material is more useful to us than almost anything else you could write about.
Yes to both, eventually. Mentors and question contributors are what the community is made of, and volunteering early is how you end up on the mentors page when it exists.
Pro is not on sale yet, so there is nothing to refund. When it opens, the refund terms will be written on the checkout page before you pay, not after.
No. We are not paid by employers, we take no placement fee, and no company pays to appear anywhere on this site. The only money here is the one price on the pricing page.
Yes. Many people expense this against a learning budget, and the invoice will carry whatever company details you need.
The newsletter at the bottom of any page. It goes out when something actually opens, which is not often, and it is the only thing that address is used for.

