Overriding the Ad Tag URL on iOS

If you need a value for your base Google IMA ad tag URL that is different than the value defined in Backlot, use the adUrlOverride function, as shown in the following example. Consider:
.
.
.
// To override the ad URL, do this *before* setting the embed code:
_adsManager.adUrlOverride = @"http://pubads.g.doubleclick.net/gampad/ads?sz=640x480...";
.
. set the embed code
.
// Remember to 'nil' it out later if need be: As long as it is non-null, the value will override any IMA settings from Backlot.
_adsManager.adUrlOverride = nil;
.
.
.