When party members are deselected/suspended, etc, they often engage in quite long processes to have themselves re-instated - because their party, and their life/role within it means quite a lots to them. Isn't it quite unusual for this deselected candidate to immediately announce a total abandonment of the party, even to the extent of announcing that they won't vote for it?
It suggests that the person's relationship with and commitment to the party was extremely slight in the first place. It seems an odd state of affairs if this is the case. You'd imagine that candidates would be people with deep and multiple ties to the party.