It sounds to me like you don't want files "BSC", "SBSCSubsystem", and "MCBTSSubsystem", but rather directories, and to have the 20041202 files prefixed with those moved into the directories? If so, try doing one category at a time: 
for my $category ("BSC", "SBSCSubsystem", "MCBTSSubsystem") {
}

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Inside the loop you'll need to:
  1. create the directory if it doesn't exist, like: 
    use Errno "EEXIST";
if (! mkdir("foo") && $! != EEXIST) { die "unable to create directory 
+foo: $!" }

    [download]
  2. find any matching files and put them in @files. I wouldn't use a regular expression; I'd just use glob.
  3. move @files into your directory. No File I/O required, rename($file, "dirname/$file") should work to move $file from the current directory into directory dirname.

Update: added use Errno

In reply to Re: Sorting names using Regular Expressions and placing them in different Files. by ysth
in thread Sorting names using Regular Expressions and placing them in different Files. by Kiran Kumar K V N

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