Project Fi intelligently shifts between multiple networks. Project Fi automatically connects you to the best available signal, whether that's Wi-Fi or one of our three 4G LTE partner networks.
You can fill out the passport application online, print it out and then bring it (along with the additional required documents) to a relevant post office. This should save you and the post office time. You may, of course, still receive and fill out the application at the post office too. let them do the rest.
There are three ways that you can get the application form -- you can pick up the application from a Post Office branch, request that Her Majesty's Passport Office (HMPO) post the application form, or fill out the application form online and have the completed application form sent to you from HMPO.