Bulk order status change with unique emails to customers

There are a variety of extensions that allow bulk order status changes.

I expect I may need to develop the code changes myself, but hopefully someone could advise which extension would be most suitable as a starting point for the following changes?

When orders are processed (in bulk) I need to notify the customer with a message that is automatic, but DEPENDENT on the SHIPPING METHOD the customer selected.

Examples:
For shipping method "Collect from Perth hub" I need to send a message: "Your order has been dispatched to the Perth hub. Please collect your order from XXXXX address on Friday between 5:30 and 7:30pm"
For shipping method "Collect from Subiaco hub" I need to send a message: "Your order has been dispatched to the Subiaco hub. Please collect your order from YYYYY address on Friday from 6pm onwards"

(The information that will go into these messages contains private home addresses, so it cannot simply be put into one of the information pages in the store)