In theory (I have not had time to try it yet), it can be upgraded to a 3.2¡± screen, in the same way as an iriginal Nanovna was upgraded (a year and a half ago, in the forum and on the nanovna wiki, I think).
You will have the same resolution but a 40% larger viewing area. No firmware should need changing although power consumption may be higher and a few more spurs may be displayed. It is a similar upgrade as the V2 vna was with the Hugen ¡°black and gold¡± v2 version.
However you have to get the appropriate 3.2¡± screen (I already have several) and need some desoldering and soldering skills, verging on on that required for smaller smd components ( to unsolder the flexible connector on the sa board and resolder the 3.2¡± screen back on. ?The 4.2¡± screen would need a firmware recompile and Eric is not minded to do this. The vnas were more open source so many people could do it and publish the modified firmware.?
Steve L