protected Instance(bool multichannel, string name, string url, string site = null, string assemblyName = null, string pathTemplates = null,
            string dashboardRelativeUrl = null, int? numberOfLicenses = null, AttendanceProtocolSettings protocolSettings = null, Status status = Status.Inactive) : this()
{
    Ensure.Arg.NotEmpty(name, nameof(name));
    Ensure.Arg.NotEmpty(url, nameof(url));
    Ensure.Arg.Match(url, Validations.Url.SimpleUrlPattern, nameof(url));
    Ensure.Arg.Is(!multichannel || site.IsNotNullOrEmpty(), nameof(site));
    Ensure.Arg.Is(!multichannel || assemblyName.IsNotNullOrEmpty(), nameof(assemblyName));
    Ensure.Arg.Is(!multichannel || pathTemplates.IsNotNullOrEmpty(), nameof(pathTemplates));
    Ensure.Arg.Is(!multichannel || dashboardRelativeUrl.IsNotNullOrEmpty(), nameof(pathTemplates));
    Ensure.Arg.Is(!multichannel || numberOfLicenses.HasValue, nameof(pathTemplates));
}