In this paper, we present some preliminary results of the first application of a fully nonlocal convection model to realistic stellar envelopes. The model has previously been studied by a detailed comparison with numerical simulations. Our first results were derived for the HeII convection zone of a 2.1 solar mass star along the evolutionary track from the zero-age main sequence to the turn-off point, thus crossing the region populated by the delta Scuti variables in the classical instability strip which are among the primary target stars proposed for the COROT programme. Although we are only able to provide a consistency test with earlier analytical results, in the near future asteroseismology may be one of the most important tools for directly testing this new generation of convection models.