**Appendix A**

The fits of *f*2 and *f*3 to the same data points (as opposed to *f*1, shown in Figure 4) are shown in Figure A1.

**Figure A1.** The plots of the upper bounds (**blue**) and lower bounds (**red**) acquired from all observations and their extrapolations via the ansatz functions *f*2 and *f*3 (shown as the dashed lines).
