All of my rider swaps ALWAYS had the date on them, so no matter what, it wasn't possible to use them another day in the first place. You couldn't get a swap and then use it the next day. You could however, use it a few hours later or later in the evening. But it had to be the same day.
It seems now there is a strict one hourish beginning and ending time from the moment the first party scans onto the ride. Pretty narrow window, but cms are all giving different rules, so who knows what it truly is right now.
It's so tricky to plan
Disneyland with small children. There are already so many variables...it would be nice if at least Disneyland knew their own logistics and could pass them on to us.