PHP Range of Times - php

Question

I need a list of times that will be used for collection times. The user will select when collections starts, ends and the intervals between these times.
If i set:
Start: 11:00
End: 20:00
Interval: 30
It will correctly produce a list from 11:00 to 20:00 with 30 minute intervals between... eg 11:00, 11:30, 12:00, ... 19.00, 19.30, 20.00
Now for the issue, if i set:
Start: 20:00
End: 03:00
Interval: 30
The following list it produced, the times are going backwards, going down from 8pm to 3am, when it should be going up! 20:00, 19:30, 19:00, ... 04.00, 03.30, 03.00
How can i adapt my code so that it always goes up? so it produces these results instead... 20:00, 20:30, 21:00, ... 02.00, 02.30, 03.00
Heres my code:
$collectTimes = array();
$range = range(strtotime($settingsCTS), strtotime($settingsCTE), $settingsCTI * 60);
foreach ($range as $time) {
$collectTimes[] = date("H:i", $time);
}

Answer 1

$startTime = strtotime('20:00');
$endTime = strtotime('03:00');
$interval = 30;
if ($endTime < $startTime) {
$endTime += 60 * 60 * 24;
}
$collectTimes = array();
$range = range($startTime, $endTime, $interval * 60);
foreach ($range as $time) {
$collectTimes[] = date("H:i", $time);
}

Answer 2

I think the code is self-explanatory, I really have nothing smart to say about it :)
$start = "20:00";
$end = "03:00";
$interval = 30;
$temp = null;
$intervals = [date("H:i",strtotime($start))];
while ( $temp !== date("H:i",strtotime($end)) ) {
$temp = date("H:i",strtotime($start." + $interval minutes"));
array_push($intervals,$temp);
$interval += 30;
}