Strain in Spain from December

The date range for the European tracker of strains found here: https://nextstrain.org/ncov/europe begins at 02 Dec 2019, and from what I can tell this strain originates in Spain. There appears to be no reporting on this that I can find. I’m assuming that this comes directly from Spanish authorities. I’m an absolute amateur at this subject, but I’d be interested to hear how there is a strain identified from this time, when the first diagnosed cases in China were from late December?