Look-ahead model

In the look-ahead model (Henke 1966), it is hypothesised that the production system scans ahead to find out which sounds are to be produced. If the specification of a sound permits it (i.e. if the sound is underspecified for the feature in question), the articulators are brought into the position necessary for the particular sound that is yet to come: e.g. the /s/ in the Dutch word 'stroop' is rounded because rounding is necessary for the upcoming vowel.

Link
Utrecht Lexicon of Linguistics