Edit your content with {} format. Then program will auto rotate your subject, and content.
I mean, my link to the invitation to register is unique, if you open it, it will be inactive for other recipients.
How to do as an example:
Hi, your bonus link for getting a promo LINK HERE ( link here - hyperlink ).
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Is it possible to make the link give constantly different for different recipients?
link here1
link here2
link here3
......