The Liste says GA2771 is 'owner unknown' formerly owned by J. A. Spranger. But I was just going through the manuscripts at Lambeth Palace Library and found 2771 there:

http://images.lambethpalacelibrary.org.uk/luna/servlet/detail/LPLIBLPL~17~17~30993~106893?sort=creator%2Ctype%2Cdate%2Ctitle&qvq=q:%3DGospel%2B;sort:creator%2Ctype%2Cdate%2Ctitle;lc:LPLIBLPL~17~17&mi=10&trs=57

The Shelf number is MS2795.

 

 

A related note about GA486. The Liste does not include the shelf number at Lambeth Palace, but it appears to be MS2794: 

http://images.lambethpalacelibrary.org.uk/luna/servlet/detail/LPLIBLPL~17~17~30863~106866?sort=creator%2Ctype%2Cdate%2Ctitle&qvq=q:date%3D15th%2BAND%2Btitle%3DJohn%2B;sort:creator%2Ctype%2Cdate%2Ctitle;lc:LPLIBLPL~17~17&mi=1&trs=24

You're right about both of these. Thank you for looking into this and letting us know. We will update the Liste accordingly.