/// <summary>
/// Only for tests!
/// </summary>
/// <returns>Start soon interval used for <see cref="_startSoonTimer"/>.</returns>
public double GetStartSoonInterval()
{
var openDate = _grbMap.NextOpenDate(_timeService.UtcNow.AddMinutes(15));
var before15Mins = openDate.Subtract(TimeSpan.FromMinutes(15));
return(before15Mins.Subtract(_timeService.UtcNow).TotalMilliseconds);
}
