I'll reply to your post:
The same idea that there must be a (short) timespan between the cry and the rapture crossed my mind several times. I can very well imagine that it plays out exactly like that. I can imagine something like 10 days due to the many similarities of the letters to Smyrna and Philadelphia - if you assign the 7 letters to the 7 branches of a menorah, they sit on the same bow ( second bow connects branch 2 and 6), hence the "10 days tribulation" may also apply for the philadelphia-like christians?
I have also been thinking many times what exactly the oil is. I came to the conclusion that the best assignment for the oil in this parable is not just "the holy spirit" but instead the "knowledge of Gods word and understanding of Gods word through the holy spirit". That's why the wise virgins can't just give from their oil in a hurry, but the foolish will have to seek (buy) it out by themselves during the great tribulation. Soon after they finally go to research the word, the Rapture happens. Understanding the end times really depends on how much you know the Bible and how much you gain understanding through the holy spirit. Jesus is the "word in the flesh" and the "a and o" (first and last letter in greek alphabet). As much as you know Jesus (the word!), the same amount he knows you. That's why he says to the foolish virgins "I never knew you", it is because they did not know the word and had no understanding in the word - they did not really know Jesus.
Watch & Pray!