Like so many other things in regards to what plants/strains do it depends on how stable they are. The single plant may be the only one to do it and they all may do it. Since that one obviously did not just do it the day the pictures were taken I would say if the others have not shown any signs so far it is unlikely they will duplicate what the one did but there is still the chance they are just slower at doing it.
Other that saying it is not an autoflowering strain I do not recall seeing anything at all about what strain it is. What is it? Possibly someone knows if it is an unstable strain or not or if it has any history of deformities.
