FujiFilm 3100ixZ - Manual (Page 29)

✻ A cartridge removed in mid-roll k
from a camera which does
not have the Mid-Roll Change function cannot be used even
if loaded into this camera.
✻ If a cartridge is removed in mid-roll j
and sent to the
processor, all frames on the entire roll will be developed.
Expose all frames on the roll before sending the cartridge to
the processor for development.
✻ The mid-way replacement of cartridges is only guaranteed
with [ENDEAVOR/FOTONEX] cameras equipped with the
MRC function manufactured by Fuji Film. There are cases
where normal operations are not possible when cartridges
containing frames exposed by MRC cameras manufactured
by other companies are used.
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