My vet will not considered neutering/spaying until 6 months due to their size.
And yes...marking and cocking their legs are two seperate things. My female MARKS...my middle "child" Reese (male)...does not and only started recently lifting his leg..baby Reggie is a marker at 5 1/2 months old. Lots of tinkle...everywhere is marking.
An un-neutered sexually mature male will make every attempt to escape should a female in your neighborhood ever go into heat. As kids...we had a beagle who would travel MILES to get to one. Once he was completely across a river...