I think this is the wrong section but I will be happy to reply.

• The MSDN subscription will last up to 3 years. If you buy it from us it goes from 2 to 3 years.
• They won't. They could suspend the account but you will be able to unlock it with a phone number.
• They won't. The product keys that have already been activated will stay active.
• It is not legal.

https://www.winstation.org/product/msdn/msdn-invite/