How Christians can think they have an idea when the end will come is opposed to Scripture
With all due respest,having an "idea" is not opposed to scripture.Predicting or prophesying is.
Scripture tells us to be "watchful, and...be mindful of the seasons".
Prophesying is? Do all those prophets in the Bible know that? Someone should have told Paul... "Pursue love, yet desire earnestly spiritual gifts, but especially that you may prophesy." I Cor. 14:1
I believe that when the time approaches, we will know. He always warned His people and I don't think He'll keep us unawares. We should be able to read the signs as they transpire.