The people who need to be worried are the members of the local constituency parties.
Their whole purpose is to get candidates elected to Parliament and local councils. They are the volunteers who fundraise, deliver leaflets and turn up on the doorstep (in marginals and 'target to win' seats).
The Labour Party has chosen to be divisive. It has picked a side, instead of mediating in a balanced way.
I am going to email my Labour CLP, if the Labour Party fails to draw attention to the one-click FPFW submission, before the cut-off date.