No -- it has be 'over time' which can be inferred to mean more than 2 hours.
How long do you infer it to be? I assumed they just meant it wouldn't beep if you momentarily stepped out of the room for 30 seconds.
I suspect "an extended period of time" will not be an hour two.
How long is that, though? I wish Apple spoke in absolutes when discussing technical details. Some people shut their phone off to golf or do some other outdoor activity, like hiking. Some rounds take close to 6 hours on public courses depending on pace of play. Imagine your friend is trying to putt then your air tagged golf bag starts going off on the 18th green.
Or lend a backpack to a friend to go on a week long camping trip?
Take the tag off the bag? Surely you can work that out for yourself whilst dreaming up these ridiculous edge cases to prove some point?