No, but it provides insight into the assumptions that the screenwriters had in place while writing the movie, which means that the movie will be based upon those assumptions whether implicitly or explicitly. It's not binding or canon, but if you know how a screenwriter thought something worked, then you have a better idea why they made the choices they did. And so there will likely be a consistency within the ideas in their work based on that foundation that, when expanding on their work, will be easier to work with than to fight since it's already underlying the piece.
If this is how Pegg sees things as going, then he wrote Beyond with that in mind, which means that any details in the script in that area are based on that assumption. Which means it all fits together in advance based on that interpretation of the changes to the timeline. So it would just save effort to use that assumption yourself as well instead of coming up with a new one. Not that you have to, just that why waste the effort unless what you have works better? And we can't know if what you have works better with Beyond until Beyond actually comes out, so at the moment literally any other interpretation is a "maybe works with Beyond" while Pegg's is a "definitely works with Beyond by definition".