That makes a *big* difference.
"more is better" as far as shaking time goes. start timing _after_ the ball is moving _freely_.
There _is_ a fairly direct correlation between longer drying times and the hardness/ durability of the finished surface. Within the same type of paint/finish, that is.
"Appliance Epoxy" does tend to "feel" tacky for a while -after- it is dry to the point of being safely handled.
Close reading of the spray can indicates it takes a _week_ for the finish to fully cure. See the notes about re-coating.