text notes in cells change leader length, text position when placed

I have an issue whereby I have a standard detail drawing that has been drawn at a scale of 1:25, as below. The text notes have all been placed with annotation scale on using a text style that ensures the finished text on the page is 1.75mm high. The detail is as per the attachment.

I then place this standard detail in my finished sheet layout at a scale of 4 as the sheet has an annotation scale of 1:100. I'll include a screenshot of the placement settings in a second post after this one. The problem is that in the placed cell, the text note leaders grow in length significantly, and the text portion of the note is shifted in relation to the leader, both horizontally and vertically.

In the original detail drawing, the leader measures 43.75mm long. When placed in the sheet, it measures 700mm which, even allowing for the 4X scale, is way way too much.

Can anyone shed any light on what might be happening?

Richard