ReadonlyadReadonlypreloadHow many seconds ahead of a midroll or postroll break to emit adPreload
(so its ad assets can be warmed before the playhead reaches it). Used only
when the break itself carries no AdBreakInfo.resolutionTimeOffset;
a break's own offset always takes precedence.
Default: 10
After an ad is set, the number of seconds to wait for playback to begin before marking the ad as failed. Default: 15