After Effects should only force you to Save As when you are opening a project file saved by an earlier version of Ae. It does this to prevent you from accidentally making that AEP unreadable by prior versions.
However, once you do that initial Save As, subsequent saves should not be Save As.
If you’re seeing this behavior every time you save, perhaps you should rest Ae’s preferences? Hold Ctrl+Alt+Shift (Windows) or Command+Option+Shift (Mac OS) while Ae is starting.
Walter Soyka
Designer & Mad Scientist at Keen Live [link]
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
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