Hi,
Just play around with PIC18F2331 recently.
I found that in the datasheet under the topic Access Bank, page 66 says that the first 96 bytes are GPR from bank 0 while the following 160 bytes are SFR from bank 15.
In page 74, this is another statement:
The Access Bank is comprised of the last 128 bytes in
Bank 15 (SFRs) and the first 128 bytes in Bank 0.
These two sections will be referred to as Access RAM
High and Access RAM Low, respectively. Figure 5-6
indicates the Access RAM areas.