Hanging semicolons in multiline statements
This is indeed purely personal, however, when you work in a group, or want to share your code, it's best to stick to certain conventions. A good source for this is:

http://www.php-fig.org/psr/psr-2

Eventhough these guidelines are quite good, I don't always follow them myself. For instance, I often use two spaces to indent, not four. Etc.

As for my personal opinion about any code: It should be very easy to read and understand. Your code wouldn't be accepted here, mainly due to the lack of comments and sometimes vague names. But that's not what your question is about. As for the concatenation dots, I like them at the end of lines:

$startOfLine = PHP_EOL.
               str_repeat(' ',$rbtSt_billToBox_leadingWidth);
$innerMargin = str_repeat(' ',$rbtSt_billToBox_innerMargin); 
extract($statementInfoArray,'stm');
$rbt .= $startOfLine.
        padBothAndTruncate($stm_bill-to-addr1,$rbtSt_billToBox_addr_maxWidth).
        $innerMargin.
        substr($stm_bill-to-code,0,$rbtSt_billToBox_acctNum_maxWidth).
        $startOfLine.
        padBothAndTruncate($stm_bill-to-city.', '.$stm_bill-to-state.' '.$stm_bill-to-zip);


and then I align all the parts on the left side. This makes it very clear what belongs together. I am however sure there are many other ways to do this.