The launch was originally scheduled for the 13 December but poor weather scuppered those plans and organisers were forced to waitfor a decent windowfor take-off.
To make a maintenance appointment, does a client need to wait at home for a 6-hour appointment window, have the technician show up late, and track mud through her freshly-cleaned carpet, no wonder she called to argue about the bill.
In the past, you had to give it an email address, waitfor the email, open it, hit the link in the body, and bring up a browser window with the boarding pass and 2D barcode.