Starting online application or finishing supporting documents first?

[maturia]

This is probably a stupid question, but I'm just wondering - if your applications are to be done online, should you have all of your supporting documents (CV, SOP, etc) done and ready to be uploaded before you begin the online application? Or should you start the online application, get a sense of how things will be done with it, and then start/continue working on the supporting documents and later return to the application to upload them in a few days or weeks? I'm just wondering if there's typically a time limit on these online applications or anything. Thanks for any advice!

[mop]

The applications can typically be saved and you can fill them out bit by bit. You don't need to do the whole thing all at once. Either way you mention is possible.