Why though? What has given you that impression?
If NSNOW/27 Years/All Together Now had wished to work with FAB, they'd have done it initially, or by now.
Feels to me that FAB will be scrambling looking for relevance and to fill the gap they're meant to fill. I've shared my views as to why I think FAB isn't fit for purpose and I have a hunch (based on the above) those within the current campaign groups will feel likewise. I mean, wasn't FABs spokesperson or chairman on Sky the other month declaring his support for the board?