Yes the tubes are "fuel compensation tubes." so I would make sure they are not blocked up with gunk etc.
From what I remember last time I cleaned this type of carby it should have another port where I have the red arrow in the pic.
This video below mentions the fuel compensation tube but calls it a capillary tube , at 51 seconds from the start.
If fuel is flowing out the compensating tubes then I would say the fuel needle and seat are not closing off properly , there should be a tiny ball on top of a brass rod the closes the fuel off in the carby but if the ball has fallen out your float level will also obviously be incorrect ,if the needle and seat are fine then I would make sure the float level is set to the correct height.
Sometimes the fuel float has a small hole or a leaking seam and fills with fuel which stops the float shutting off the fuel.