Good

The only issue is shipment info lacks flexibility.
It would be better to have a single text block with replacements.
For example:
“Your order was shipped via {provider_name}.
Tracking number is {tracking_number}.
Click here to track your order: {tracking_url}.
It may take a few days before the status information becomes available.”

I just tweaked the message in bst-tracking.php / display_tracking_info().

Thanks!