Great Northern 4-8-4 Aster

Will Aster bring back the model of Great Northern S2 Northern in the near future.
First Aster is now "Aster Hobby" a sub-brand (subsidiary?) of Accucraft UK Limited. From their site, "Ultimately, Aster Hobby will continue to supply the Gauge 1 hobby with top of the line collectable live steam models for many years to come. "

With that statement I would say the short answer is "no". Things sold as collectable are generally produced in limited numbers and not re-run (otherwise the originals would not be collectable anymore). In the far future they might retool a new version.