If you want a flatish route towards Dover you're best off staying just slightly south of the M20 at all times until after Ashford, then personally I would head down the B2067 towards Hyde before taking the coast road back up to Dover/wherever.
@Sam started
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If you want a flatish route towards Dover you're best off staying just slightly south of the M20 at all times until after Ashford, then personally I would head down the B2067 towards Hyde before taking the coast road back up to Dover/wherever.