I don't have that sail. But I have about dozen severne race sails.
What sometimes happen with excessive batten tension, from the cam rotation, is the end of the plastic ferule pops off. Then the front batten slides. Ideally replace the ferule. But now I don't bother sourcing those fiddly parts instead I prepare the surface with 80 grit, and use a little bit of glass and UV epoxy, to make a sleeve for the ferule, like this.

For working out the length, the tapered batten comes all the way to where, the plastic end used to be.