Hi. For example here: Filament change during a print results in layer shift. Just search for “filament change p1p”.
Also without AMS you can add a second filament in Bambu Studio and “paint” the model. At the layer where you want to change the filament, you have to add “custom code” and insert:
M400 U1 ;pause and wait for resume pressed
G28 X Y ;home XY
M106 S255 ;restart part cooling fan if needed
Then the printer will pause at the layer and wait for user input. Now you can “unload” the old filament and “load” the new filament. After this press “resume”.
Because of a firmware bug you can’t simply use “add pause” because the “load” function caused a layer shift (about 1 mm) on resume printing. The custom code will work around this bug.