One theory about this entry is that it was a sort of mistake, that her day of death was listed as the day of her profession, or maybe the day of her profession into the order keeping this necrology. At first I thought that was absurd, but if you look in the left column, towards the top, #232 is listed as having died in 1962, so there does seem to be some practice of recording the dead nun by a different year from her actual death. Sr. Lucy doesn't seem to be the only one with an anomalous year given for her death.
On the whole I don't think it's that convincing, but it sure is a tantalizing piece of evidence.