I haven't been able to find a closer view of Princess Olga at the 1955 wedding. Below is an enlargement from a photo showing a large group at the church door.
I think that the tiara is the same as it appeared in earlier years.
When I zoomed in on a photo from 1962, I realised that the hanging diamonds are still there.
I suspect that the upper layer of the tiara was repositioned so that there is a gap between the lower section and the upper.
What do others think?
On the left is a 1962 photo; on the right a 1937 photo.