I recently did 2nd servicing for my Avenger. I did a full tank and found that there is a fuel leak from tank overflow outlet (not carb overflow pipe). I have done full tank several times before and have never observed this. When I checked with service station they first of all did not agree that such a thing can happen, but when I proved, they told me it is common to see in bikes when a tank full is done and this is a feature of BS4 safety where there is a hole at tank cap from where excess petrol flows away via a filter fitted at outlet.

I don’t find this genuine as this should have happened in past full tank instances as well.

Any views here?