The BLM now has the duplicate GLO plats for Nebraska scanned and on their website. The Nebraska State Surveyor's Office (SSO) has had our copy of the GLO plats also online. I've compared a few and noticed the plats vary in what was placed on them. We also have a full sized set of GLO plats for Lancaster County in our office and they look different from the BLM and SSO plats. The numbers are the same, but sometimes there are notes where an error or discrepancy was found and noted on one plat, but not the others.
Here is an example of the BLM plat and the SSO plat of the same township.
http://www.sso.nebraska.gov/pdf/gloc/1721.pdf
Have the same thing here in Arizona. Our DOT has copies of some that contain more recent notes than the BLM has...
I would imagine it to be the same case seen of records in many offices.
When copies of maps were needed, a draftsman, surveyor or scrivener copied the originals and would add side notes and other references not on the originals for their own use.
In the early 1970s I worked for a surveyor that refused to pay for copies and had me or who ever was doing research to transcribe the deed information and draft the drawings of record.
:gammon: