Just because the patent for utility model is accepted does not mean that it will be granted. It depends on whether your application needs to be revised, whether anyone has any objection to your patent application, and so on. Generally, the results will be produced within 3 to 6 months. The utility model patent is a procedural review and should be simpler.
If there is an invention patent, it will take at least one year, because the substantive examination of the invention patent is much more complicated.