"When the squad hops into town" achievement triggers after getting each frog on a lead one at a time, not all at once.

The achievement for "get every type of frog on a lead" doesn't require all the frogs to be on leads at the same time. I had some white and orange ones on leads earlier, and I just put a green one on a lead and got the achievement. 

Is this intended behavior? Personally, I think the achievement ought to require you to have them all in one place, so the squad is all in one place. That seems like the intent, and it's what I thought the achievement was supposed to be for.