This paper proposes a new solution for autonomous decision-making in the RAT selection process in multi-service multi-access network scenarios. It is based on exploiting the time dimension in the RAT selection, so that, based on the current mobile terminal and network context and its future evolution, terminals can choose the appropriate initiation time to start a given transmission, waiting for the arrival to the coverage area of the most suitable RAT. The proposed strategy is claimed to have applicability for non-real time services without stringent deadline constraints (e.g. e-mails, downloading MP3 files, etc.). The algorithm is evaluated through simulations in different scenarios, revealing that it provides remarkable capacity increases, while at the same time ensuring that non real time transmissions do not exceed specific delay bounds.