So I feel crazy asking all these questions but I guess thats what this forum is for.
I understand the whole propagation process and that it will take up to 72 hours to complete. My questions comes with something my hosting company provides me. Hawk Host gives me a "temporary url which you may use to view your website and upload files" while the propagation is taking place. My question is if I use the temporary url to upload files through my cpanel - i.e. http://temporaryurl/cpanel - will this automatically be reflected in my actual url once the propagation has taken place?
The short answer is yes. But as Mike said, some php scripts will not work from a temporary URL.
For example, if you were to install wordpress. Be careful about scripts that automatically populate the working path. For example, if a script takes http://188.8.131.52/~username/script_folder as the working path, then it might not work correctly when you try and go to it from the propagated domain name, depending on your servers configuration.
normally, temporary URL only showing the website in the server only. If you upload any file to your server, you can view it using temporary URL during domain propagation period.
After it is fully propagated, you can view from your actual website.
The same zone for propagation period is after 72 hours as it makes sure the domain is fully propagated to the server. otherwise u might able to view it, and some of your visitors aren't able to view it.
You can use a DNS checker to check whether the domain is propagated or not.
Actually it depends on your ISP and whether they actually abide by TTLs or if they simply choose to cache things for 24, 48, 72 hours or more.
I have the TTLs on most of my important domains set to something like 1 or 2 hours and in most places and on most ISPs if I make a change it propagates pretty quick as fast as a few minutes to as slow as 1 or 2 hours (my TTLs) but some ISPs will simply carry your old zone until a certain period of time they have configured passes.
For people on ISPs with poor caching policies I usually recommend OpenDNS.