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In this section we explore the dynamics of the thin film on different hydrophilic- hydrophobic heterogeneous substrates. Our aim is to examine the effect of a hydrophilic pattern imposed on a hydrophobic substrate on the dynamics of the film. Furthermore, taking into account the periodicity of the front, we will focus on patterns of characteristic lengthscales which are comparable to Λ$_{max}$( θ$_{e}$ = 90 ◦ ). 

## A. Longitudinal stripes 

In many situations, such as in microfluidic flow guiding and filamenting [2, 9], it is desirable to orient the growth of the contact line on a prescribed direction. For substrates with spatially varying wetting properties, the flow is expected to orient toward the more hydrophilic regions due to their lower flow resistance. Meanwhile, the front is expected to destabilize on the hydrophobic stripes if their width is of the order of the most unstable wavelength, Λ$_{max}$( θ$_{e}$ = 90 ◦ ) . Hence, our main interest will be to examine the effect of the 

