Found it !
Thx for the feedback guys
Just realized that the ECAM proc. has a typical Airbus brackets right after the condition I was asking about before. The one that stopped me from "using" this proc. IF my fuel WAS NOT JET A.
Literally, each statement leading to a XFR pops-up " IF JET A fuel loaded, starting FROM -40°c. And right after that, u can read : " ( not displayed at -47°c )"
Meaning, that JET A WILL NOT SHOW if we give it a chance for the Temp. To lower a bit further than that ( til -47°c ), in which case we are now ( literally again ) entitled to do the so long desired XFR for our type of fuel ( normally not JET A but JET A1 )