If anyone is using rtl_433 to decode TPMS from Citroen or Jeep, please
look at
https://github.com/merbanan/rtl_433/issues/3364
which is attempting to reduce (consideable) confusion about what the
encoding really it. In particular, if nobody is using Citroen, then
it's likely that how I thought it worked in 2017 will get very little
weight in revisions.