In a world of email and electronic communication, an official-looking letter carries extra credibility.
When what looks to be a bill reminding me of the need to renew the prstudies.com domain arrived, correctly addressed to me, I wondered whether I needed to act. I had only changed the registrar last year so at first sight this letter looked believable.
The only thing is, it's not from my registrar. The information that gave the letter credibility (the domain name, my name and address) are all in the public WHOIS record – exposing the limits of transparency.
This is an attempt to snare business unwittingly. On re-reading the letter it's carefully worded ('as a courtesy to domain name holders…') to avoid untruths – but you can be legal and still unethical.
It's another example of legal advice running counter to public relations advice. This is a reputational issue: Google search results give many warnings of this attempted scam, so I'm posting this to add my voice.
PR Studies 
I remember getting one of those letters this time last year. At first I was quite worried but then realised I had the domain on auto-renewal. Did feel very misguided but I can’t imagine lots of people falling for this scam. Most people who own domains will probably realise as you and I have done.