anton-luigi and Jeff,
What will generally dictate the useful life of a dough is the amount of yeast used and the temperature of the dough during fermentation. The degree of hydration of the dough and the amount of salt used will also have an effect on the window of usability but unless the hydration and salt levels are out of the normal ranges under the circumstances (e.g., extremely high hydration for the type of flour used, or very high or very low salt levels), and all else being equal, the amount of yeast used and the dough fermentation temperature will be the key determinants of the useful life of the dough. In anton-luigi's specific case, the rest periods (autolyse and non-autolyse rest periods) will also affect the useful life of the dough by jump starting the fermentation process before the dough is stored (in anton-luigi's case, in the refrigerator).
The above rules will apply whether one is using commercial yeast or a natural starter or preferment. However, commercial yeasts will usually produce more consistent results. This, along with convenience, is why commercial yeasts, especially dry yeasts, were developed in the first place (starting with ADY around World War II). With natural starters/preferments, it is often less certain how long the dough will be usable. That is because of the many different varieties and strains of natural starters, their method of management (including activation and feeding), their level of hydration (e.g, stiff or loose), their level of activity at the time of use, the amount used, and so forth. These factors, along with the dough fermentation temperature, whether at room temperature, in the refrigerator, or some combination of both, will generally dictate how long the dough is usable. It is possible for a dough leavened with a natural starter/preferment to overferment and become unusable. To satisfy myself that that could happen, I once ran a test to confirm it. It is prudent, therefore, to watch the dough as it ages to be sure that it doesn't become too wet (due to the release of water from its bond), slack, gassy, and too pancake-like as the gluten structure is degraded by the action of enzymes (protease).
I hope anton-luigi will keep us informed of his progress on this matter.