There is no "target nearest to the cursor," it dashes towards a targetted enemy that is under the cursor otherwise it will dash infront of her. It does not auto acquire targets like Yasuo's Last Breath.
I took into account the timeout interval of the third stack rather than the application ending the moment said stack was applied. It feels like it's over the duration, but 1.5 seconds seems more pertinent.
you recently made some edits to the channel page, namely putting pyke in the charged abilities box (probably right, i'm not a PBE guy) and also redefining some of the other guys in that box from classic channels to movement channels. I just wanted to doublecheck that you realized that classic and movement doesn't mean whether you can move during the chargeup but rather that classic channels are stopped by cast-inhibiting CC whereas movement channels are also stopped by roots. If you knew this, and tested these to see whether they were stopped by roots that's fine, but i'm pretty sure some of those (such as varus and xerath) although they move during the charge, the charge is not stopped by roots.