Yes, you can.
In order to be a legally binding contract, three things are required: an offer, acceptance, and consideration. Consideration is the value gained by entrants into a contract.
In short, if you did not pay to license some piece of open source software, there is no consideration for the author of that software. Hence, the license attached to the software is NOT a contract binding on the author. It is a bare license -- simply the terms under which you are permitted to use the author's IP -- and the author is legally entitled to revoke it at any time.
You may not like it, and it has unfortunate implications for open source, but that's how contract law in common law jurisdictions like the USA works.
https://lulz.com/linux-devs-threaten-killswitch-coc-controve...
I haven't the slightest clue what you're taking about. You can change your license on future versions, but you can't retroactively change the conditions of an offer that's already been accepted.
If you're talking about the ability to delete published packages from NPM, that's entirely unrelated to licensing.