1. Register the new round event.
2. In that functions add 1 to the round count variable.
3. In your admin command function, check if your round count variable is greater than 3 (or greater than or equal to 3). If not true then return PLUGIN_HANDLED.
Semi-pseudo code

:
PHP Code:
new g_iRoundCount = 0
public plugin_init()
{
// ....
// Register NewRound to call function eventNewRound
// ....
}
public eventNewRound()
{
g_iRoundCount++
}
public my_admin_command(id,level,cid)
{
if(g_iRoundCount < 3)
{
return PLUGIN_HANDLED
}
// ....
}
Also, you could register the round end log event and increment there instead.
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