For the purposes of SD-6, I think we want two values: 201803L for the original addition of <span> by P0122R7 (Jacksonville, 2018) and then 201902L for the API changes from P1024R3 (Kona, 2019). The C++ working draft only needs the newer value.

Proposed resolution:

Add a row to [tab:support.ft] in [support.limits.general]:

__cpp_lib_span  201902L  <span>