Why does my power drop for a moment when starting to go up hill?

Stryd can currently not detect incline, but used elevation to calculate the correct power level. Stryd currently needs about 15 seconds to detect the incline accurately without being noisy and making power unstable (based on elevation gain). It takes Stryd about 15 seconds after you start going up hill to accurately detect the slope, meanwhile it only takes about 3 seconds for Stryd to detect the change in pace. We choose to do it this way to best achieve realtime responsiveness and stability of the power number from Stryd, and we are working now to reduce that 15 second delay when encountering a hill in future version of the software.