// Does it occur on target date?
if ((this.pattern.weekdays & p.date.get.dotw(h.target)))
{
    // How many week has it been since this appointment started?
    var weeksSinceStart = p.date.get.weeksBetween(h.current, h.target);

    // Skip this week?
    if (weeksSinceStart % this.pattern.periodicity)
    {
        return null;
    }

    // How many blind occurrences are there?
    // e.g. appointment starts on a WED but the pattern is MO/_WED_/TH/SU = 1 blind (MO)
    var blind_occurrences = 0;

    // Avoid loop with clever switch
    switch ((this.pattern.weekdays & p.date.get.dotw(this.start)))
    {
        // INTENTIONAL FALL-THROUGHS!!! //                                                                                                                    
        case FLAG_SUNDAY:
            (this.pattern.weekdays & FLAG_SATURDAY) && blind_occurrences++;
        case FLAG_SATURDAY:
            (this.pattern.weekdays & FLAG_FRIDAY) && blind_occurrences++;
        case FLAG_FRIDAY:
            (this.pattern.weekdays & FLAG_THURSDAY) && blind_occurrences++;
        case FLAG_THURSDAY:
            (this.pattern.weekdays & FLAG_WEDNESDAY) && blind_occurrences++;
        case FLAG_WEDNESDAY:
            (this.pattern.weekdays & FLAG_TUESDAY) && blind_occurrences++;
        case FLAG_TUESDAY:
            (this.pattern.weekdays & FLAG_MONDAY) && blind_occurrences++;
    }

    // How often has it already occurred *this* week?
    var occurrenceIndexThisWeek = -blind_occurrences;

    // Avoid loop with clever switch
    switch ((this.pattern.weekdays & p.date.get.dotw(h.target)))
    {
        // INTENTIONAL FALL-THROUGHS!!! //                                                                                                                     
        case FLAG_SUNDAY:
            (this.pattern.weekdays & FLAG_SATURDAY) && occurrenceIndexThisWeek++;
        case FLAG_SATURDAY:
            (this.pattern.weekdays & FLAG_FRIDAY) && occurrenceIndexThisWeek++;
        case FLAG_FRIDAY:
            (this.pattern.weekdays & FLAG_THURSDAY) && occurrenceIndexThisWeek++;
        case FLAG_THURSDAY:
            (this.pattern.weekdays & FLAG_WEDNESDAY) && occurrenceIndexThisWeek++;
        case FLAG_WEDNESDAY:
            (this.pattern.weekdays & FLAG_TUESDAY) && occurrenceIndexThisWeek++;
        case FLAG_TUESDAY:
            (this.pattern.weekdays & FLAG_MONDAY) && occurrenceIndexThisWeek++;
    }

    // Set index
    var index = (weeksSinceStart * this.occurrencesPerWeek / this.pattern.periodicity) + occurrenceIndexThisWeek;