The amount of time doesn't matter. I believe no one ever died before he would have repented. God gives us all we need to come to him. Some do. Some don't.
The error of the unbeliever is expressed in the saying, "Though having eyes, seeing not."
So... Infants who die would have been life-long evil had they lived a full life?
Khmer Rouge embraces Jesus
The Khmer Rouge followed a harsh brand of communism, killing nearly two million people in their bid to return Cambodia to Year Zero. Now they have a new faith: evangelical Christianity.
Hundreds of former fighters have been baptised in the past year. The Khmer Rouge's mountain stronghold, the town of Pailin in south-west Cambodia, has four churches, all with pastors and growing congregations. At least 2,000 of those who followed Pol Pot, the guerrillas' former leader who died six years ago, now worship Jesus. [end of excerpt]
And from that same thread, post 33:
Christianity had a rough start in Cambodia; the bible wasn't fully translated into Khmer until about 1964, IIRC.
The coup which overthrew Sihanouk was followed by Christian growth, so that by the time Cambodia fell to the Khmer Rouge, there were some 30 Protestant churches in Phnom Penn (a growth factor of 10, in a period of 5 years).
The President of the Supreme Court and various other individuals had become believers in "the new God". All of this was swept away with the fall of the city;
Do we have a situation here where the truly repentant Khmer who converted will go to Heaven?
Will their victims go to Hell forever?
Do you think it likely that some of the 2 million victims might have converted to Christianity had the Khmer not murdered them?