When will SE be down? SE will be down/read only today 2017-05-04 at 00:00 UTC until 00:20 UTC.

Your challenge is to output a truthy value if SE is down/read only and a falsy value if SE is not. You may not have any input, and you must use date builtins to determine if SE is down/read only (no actually querying the SE api!) Example output:

12:34 UTC 03 May 2017 -&gt; false

00:00 UTC 04 May 2017 -&gt; true

00:20 UTC 20 May 2017 -&gt; undefined, see below


That's undefined behavior, because it's too far after the window of time. 
 To be clear, you can assume your program will be run from UTC 8:00 today (5/3/17) to UTC 1:00 tomorrow (5/4/17).

00:21 UTC 04 May 2017 -&gt; false

00:20 UTC 04 May 2017 -&gt; true

00:10 UTC 04 May 2017 -&gt; true


Note that any truthy or falsy values are allowed, not just true and false. You must be accurate to the nearest second, and no changing the system clock! You may assume that your program is being run on a machine on the +0 UTC time zone.
JavaScript (ES6), 26 24 23 22 21 bytes

Saved 3 bytes thanks to Shaggy and 1 byte thanks to Luke.

_=&gt;new Date/12e5%72&lt;1


Checks if time passed in current day is less than 1200000ms (1200s or 20min). Assumes downtime to be 20 minutes not 21, which appears to be the case in the linked post. 00:20UTC is the exclusive upper bound.