Submitting an update of a plugin prior to review

Can anyone tell me about how I would reload my plugin once it is submitted. I added a plugin 7 days ago and it is now waiting review. I added some amazing updates to it and better instructions so now I would like to send up the “better” version of the plugin.

I looked around the FAQs etcc. with no avail. Does anyone have any insight on this or do I just have to wait to get rejected and then upload the new version — or will they let me without changing the name and everything. i.e. How many versions do they let you send up for review…