An almost complete mystery (feature)

An almost complete mystery was the ninth in a line of clues in the series known as the #FindTheDoctor mystery released in late 2021.

It had the letter  N  as the clue.

Display
An unknown object, dubbed EPDUPSXIPNBH-TFQU, has been acquired by the Natural History Museum and has been said to be cause of intense speculation and discussion and therefore not put on display.

It is described as being of metallic origin encased in yellow amber.

Worldbuilding

 * The object is mentioned as being of a metallic structure.

Story notes

 * The letter  N  in the word currently in the text is in capital.
 * Curiously, EPDUPSXIPNBH-TFQU, if put as a caesar cypher spells out DOCTORWHOMAG-SEPT, referencing the Doctor Who Magazine issue from September 2021, DWM 569.