> therefore would loose the sycronisation path with the Satellite and loss of ACARS transmission.
While quite possible, not necessarily in this case. The target satellite was effectively directly overhead, and the antenna beam angle is around 60 degrees. So in a flat spin that is horizontal there should only be a few degrees of wobble in the bird position, and that probably wouldn't even be detectable as a gain change.
If the link was lost for other reasons, I suspect that it might be recovered moderately easily since the bird wouldn't be moving much in terms of antenna steering angle.