GBPCAD - can simple box become box on steroids?

With over 80% bullish sentiment, this one calls for shorts (besides GBPCHF and GBPUSD). Trade plan here is very simple - open shorts in red area, SL somewhere around 30 pips, move SL to BE when it closes below box centre, offload half of position in green area, leave the second half to run. Eventually I expect this pair to go lower (see weekly bird view chart below) and that's where the remaining half of position would bring nice pips.
If conditions will be OK, I will consider also adding to short position after breakdown of the box lower side and re-test it again.

Bird view:

Disclaimer: this idea is solely for my own purposes, to satisfy the ego, if it will work out ;)

Trade active:

Shorted inside red box.

Trade closed: stop reached:

SL reached :(