Dehydration of α-allyl methyl alcohols catalyzed by linalool dehydratase isomerase (LinD) provides a straightforward route to alkene synthesis. While previous studies have shown that LinD exhibits high enantioselectivity, exclusively converting the S-enantiomer to β-myrcene as the sole alkene product, our findings reveal that this selectivity is restricted to the early stages of the preparative enzymatic synthesis. As the reaction proceeds, we observe the formation of the thermodynamically favored Saytzeff olefin, indicating that LinD's catalytic profile is more versatile than previously recognized. Molecular dynamics (MD) simulations rationalize the observed enantioselectivity of the enzyme and further support the shift in selectivity during the reaction. A comprehensive synthetic approach demonstrates that this phenomenon enables selective access to both Saytzeff and Hofmann alkenes using the same enzyme. Overall, this study showcases the practical utility of LinD for selective alkene formation, including from non-natural substrates, and challenges the prevailing understanding of its catalytic properties and stereochemical selectivity. By integrating insights from biochemistry to large-scale synthesis for applications, these results reveal the potential for unexpected enzymatic behaviors and suggest that the current understanding of LinD should be expanded to incorporate additional perspectives.