Timed jamey try this

#include "ScriptPCH.h"

class PvP_Event_Announcer : public WorldScript
{
public:
    PvP_Event_Announcer() : WorldScript("PvP_Event_Announcer"){}

    void OnStartup()
    {
        Events.ScheduleEvent(COUNTDOWN_60, 900000);
    }

    void OnUpdate(uint32 diff)
    {
        Events.Update(diff);
        while (uint32 eventId = Events.ExecuteEvent())
        {
            switch (eventId)
            {
            case COUNTDOWN_60:
                {
                    sWorld->SendServerMessage(SERVER_MSG_STRING, "|cffffcc00[PvP Event Announcer]:|r|c00FFFFFFThe 1 versus 1 PvP event countdown is starting in 1 minute !");
                    Events.ScheduleEvent(COUNTDOWN_30, 30000);
                    break;
                }
            case COUNTDOWN_30:
                {
                    sWorld->SendServerMessage(SERVER_MSG_STRING, "|cffffcc00[PvP Event Announcer]:|r|c00FFFFFFThe 1 versus 1 PvP event countdown is starting in 30 seconds, contestors be ready!");
                    Events.ScheduleEvent(EVENT_START_60, 30000);
                    break;
                }
            case EVENT_START_60:
                {
                    sWorld->SendServerMessage(SERVER_MSG_STRING, "|cffffcc00[PvP Event Announcer]:|r|c00FFFFFFThe 1 versus 1 PvP event countdown has started, you have 1 minute to enter by typing: .enterpvp , be fast cause only 10 players can enter!");
                    Events.ScheduleEvent(EVENT_START_30, 30000);
                    break;
                }
            case EVENT_START_30:
                {
                    sWorld->SendServerMessage(SERVER_MSG_STRING, "|cffffcc00[PvP Event Announcer]:|r|c00FFFFFFThe 1 versus 1 PvP event countdown is only 30 seconds more, enter fast if you still want to by typing : .enterpvp");
                    Events.ScheduleEvent(EVENT_START, 30000);
                    break;
                }
            case EVENT_START:
                {
                    sWorld->SendServerMessage(SERVER_MSG_STRING, "|cffffcc00[PvP Event Announcer]:|r|c00FFFFFFThe 1 versus 1 PvP event has started !");
                    // Events.ScheduleEvent(EVENT_END, 60000);
                    break;
                }
            }
        }
    }

private:
    EventMap Events;

    enum eEvents
    {
        COUNTDOWN_60,
        COUNTDOWN_30,
        EVENT_START_60,
        EVENT_START_30,
        EVENT_START,
    };

};

void AddSC_TimedTest()
{
    new PvP_Event_Announcer;
}