My youngest ones went back to school today too (first and third grades) so I'll have a cup of virtual coffee with you. I think back to school is harder on the parents than the kids.
Last year I was not happy about one of the teachers assigned, for weeks kept a close eye on everything he did. And you know what? He turned out to be a super teacher.
As for the GATE assignment, why don't you send an email to the principal and ask for an update. At our school the gifted classes start a couple of weeks into the school year. I'm sure if he skipped a grade, he qualifies for GATE!