I knew I had answered this question better somewhere else some time ago, finally found it:
Almost all these question regarding timestamp and server time, like this question, relates to how Dreamweaver sorts out the server time. All version of Dreamweaver (at least since version 3) creates a temporary folder on the same level ftp connects to. This folder is named 'XYIZNWSK'. Old versions of Dreamweaver will try to create this folder up to 20 times, which will explain very long time attempting to connect. Newer version of Dreamweaver tries this once.
If you have defined a folder on the remote that you don't have write permission to, you will not be able to determine server time. For example if you've defined the remote server to a upper level folder, and your site files belong in a subfolder like public_html, httpdocs, www, or similar, you will experience this problem. Solution: Take that exact folder name and put it in the "Host Directory" box of the remote info in the site definition. Adjust the local site folder down a level, if
needed. Now dreamweaver can write to the directory it logs into (create the temporary folder), and can determine the server time.