Mine is 5 months and still does the strech and pee....wind of course almost makes it his his front legs. :0
My boy won't pee or poo on walks unless desperate. He wants to go to his spot on side of house. Good Thing is now he views lawn as food and rocks as potty so my grass now might live after all!!! Yay!!!Panzer lifted his leg once when he was pretty young like that too, but hasn't done it quite like that again! I was so tickled when I saw it that I called my husband at work (our boy is growing up! )
Nowadays, at 7 months, he'll lift his leg about an inch off the ground. He doesn't mark anything and rarely goes potty at all when we're out & about. Fine with me!