One of our birders made these three photos of a small white heron (egret) in a very well-birded urban hotspot in Belgrade. The most logical choice in our area is Egretta garzetta, although they are already leaving for south (mostly summer visitors). However, several persons remarked that this bird looks strange and some have suggested Egretta gularis or a hybrid.
If you are familiar with the other two forms, may you please judge this bird?
Thank you in advance.