Hi,
We usually wait for 2 weeks between the release and the activation of the update.
That's to ensure that we catch all of the main issues with a release for people updating their live website without properly testing it on a copy of their website first.
The 5.0.1 was released last week and thus we didn't activate the auto update.
Now, we published the 5.0.2 as a security release within that 2 weeks time frame. We still waited for a whole day before activating the auto update, just in case. We've activated the update system today, so you will soon be prompted by your Joomla.
In any case, don't worry.