Hello Xard,

is this a valid signal, please?

XARD: Yes, it is a valid signal - as long as the TREND line is intact and it was showing DOWN so a sell signal is valid.
Please use the latest version as it shows the Ribbon between the TREND and SIGNAL lines.
Today's move was a repeat of two trading days ago where price crossed above the TREND line but the DOWN TREND was still in play and we see price turning back down again.