There are multiple possible dates because the radiocarbon date of 5568 BP intercepts the calibration curve at more than one point. Due to the perturbations in the absorption of radiocarbon over the millennia, the variance is sometimes full of wiggles on the curve, so placement can occur at two or more points.

Are radiocarbon dates exactly the same as calendar dates to the year?

Archaeologists generally rely on radiocarbon dating to determine the age of such artifacts as bones, charcoal or wood. But one radiocarbon year is not the same as one calendar year. Radiocarbon dating works because all living things absorb carbon from the atmosphere around them.