Where did Apple's serial number wp begin to be produced?

Apple serial numbers generally don't start with wp.

In most cases, CH is China Bank, ZP is Hong Kong Bank, LL is American version, JP/J is Japanese version, KH is Korean version, ZA is Singaporean, and TA is Taiwan Province Province. B is Britain, C is Canada, X is Australia and F is France. M starts with a retail machine, n starts with an official turnover machine, f starts with an official turnover machine, and 3A starts with a demonstration machine; C stands for Foxconn Shenzhen production, F 1, F2 and FK stand for Foxconn Zhengzhou production, G0, F4H and F77 stand for Heshuo Shanghai production, DNP stands for Foxconn Chengdu production, and G6 stands for Foxconn Shenzhen new production line.

Every Apple mobile phone will be assigned a serial number when it leaves the factory, which is equivalent to our ID number. Each serial number is bound to only one device. The serial number can be used to check whether the equipment is genuine or brand new and unopened. The letters and numbers in the serial number have corresponding meanings, such as production batch, equipment model color, production year, etc.