Of course they have a standard evidence pack, it would be expensive to craft a unique response to each case. The duplicate letters seems odd unless they are reminder letters, if they have the same reference it's only one PCN, don't over think it, their systems will be automated so it's unlikely to be human error.
As for the email, you sent a query via their privacy form and received a reply confirming it will be dealt with by their privacy team, not really that odd.