XIAO Expansion Board and Onboard Interupts

I want to utilize the interrupt output capability of the PCF8563 Real Time clock built into the Seeeduino XIAO expansion board. The expansion board circuit diagram shows the IRQ line coming out of pin 3 and going to TP2, but what TP2 is, is not clear to me. And it does not show up anywhere else on the diagram. Does anyone know exactly where on the expansion board I can get the output from pin 3 of the PCF8563?

Thank you