I battle with the idea that this was a "goodbye" as it's meaning would not have come across, unless there was a note sent with the flowers (can't find any reports that mention this)?
Was the date itself significant between herself and her Stepmother? Possibly a secret only they knew? Possibly a date that Karen Wilson has not considered? Was it a thank you? For example, was it the date the previous year that she found out about the circumstances surrounding her Mother's death (this would be with the assumption that it was Karen Wilson that told her or said something that made Ruth delve into her Mother's death)? Or perhaps, something as simple as a truth or statement said that resonated with Ruth. Or perhaps a thank you for what was going to happen on that day?
I do not believe you would choose a specific delivery date, unless the date itself held meaning between you and the receiver (not necessarily profund, such as a birthday) or unless you didn't believe that person would be at home to receive them until that time.
I agree that the date has to have some meaning, and if it does, neither Karen or Ian is telling.
According
to this article in The Sun:
"Ruth had been told she died after falling down the stairs and breaking her neck, but in October 1995 she went to London to examine her mother's death certificate."
This is just one month before her disappearance—not a year—and this is
confirmed by one of Ruth's friends:
"Crucially, Catherine revealed that Ruth had found out about her mother’s suicide just before she disappeared. She was devastated. 'Ruth was really troubled,' she said. 'She had so much going on in her head that she was desperately trying to find out who she was. '"
My first thought, then, was: what if the delivery date was exactly one month after she examined the death certificate? But
October 29 was a Sunday that year, so I doubt a library or public records place would've been open. (But could she maybe have gone on Friday, October 27, exactly one month before her disappearance?)
Another thought is that maybe the date is connected to the wedding anniversary of her father and stepmother. I've read that they were married "
in the last quarter of 1983 in Surrey," i.e., October–December 1983. Maybe October/November 27/29?
I haven't found their marriage certificate, but Nesta's death certificate is public (see below). And I note that it was "certified to be a true copy" (whatever that means) on November 21, 2017—almost exactly two years before Ruth disappeared.
As for the meaning behind the flowers,
Catherine agrees that they were a "dark practical joke," adding that they were a "two-fingers up kinda thing." I don't know what to make of that, though. Did Ruth blame Karen for maybe helping to cover up the truth about Nesta's death? But is that something Ian would've told Karen to begin with, like "hey, my first wife committed suicide." If the flowers are connected to Karen and Ian's wedding, could it have been a way for Ruth to slight her father, by addressing the flowers to Karen alone? That would qualify as a "two-fingers up kinda thing" for me.