The focus of this issue must not be upon Christian survival, but rather survival of the Jews as part of the process leading them to their ultimate redemption. We must be clear, that the underlying motivation for such practical preparation and other actions related to hiding or fleeing is not for the Church to save its own hide, so to speak, but as it relates to Israel's ultimate redemption through their witness, and the insight in "understanding the times" as well as the practical applications. But, in both cases, The Church will be God's vehicle in revealing Christ in word and deed. Where does the Spirit's leading enter in? Those with the greater maturity, insight, and gifting, will especially be required to know the Spirit's leading, and as a whole, I believe they will. No doubt, there are general principles revealed in Scripture, but for some, and quite possibly a relative few, it will be a matter of the principle applied at the individual level, "What is that to you? You follow Me!"
There will be a very small remnant called to remain in the city for greater purposes outside of themselves. During the great persecution following Stephens martyrdom, though much, if not the majority of believers fled Jerusalem and Judea and scattered to other regions, bringing the gospel with them, the apostles, nevertheless, remained in Jerusalem. At that particular time in the history of the early Church, and quite likely unbeknownst to the vast majority, though the common thought was in fleeing for their lives, it was God sovereign plan to use this persecution as a "practical" impetus to spread the gospel far and wide, to extend the witness and testimony to all peoples of all nations.
These were the same men who not long ago fled in fear upon Jesus' arrest. Among them was Peter who had denied the Lord 3 times. They had every justifiable reason to flee as well, and no one would have begrudged them of that. In fact, it was quite likely that were exhorted to flee by other well-meaning believers. It may even be that Peter recalled how he tried, to no avail, to convince Jesus that He shouldn't go to Jerusalem to die. And, we all know the sharp rebuke Peter received in return, to his shock and hurt. For some, maturing into Sonship will be of utmost importance, "For those who are led by the Spirit of God shall called the sons of God." They will need not only to "discern the times" for others, but also as it related to themselves in sensing where they are to be strategically placed according to God's purposes. For many, they will be called to fulfill the statement, "And they loved not their lives unto death."
Well, these are just a few thoughts, which in reality, is but scratching the surface. Needless to say, there is so much more. There is always so much more as men "looking through a glass darkly." But, it is also imperative to first lay a sound foundation from which to build upon as it relates to God's purposes, in both perspective and practical preparation. These 2 factors are inextricably linked as illustrated by the description of the Tribe of Issachar as "Men who understood the times and knew what Israel was to do." The principle is clear. They "understood the times" which resulted in prudent action, "was to do." Revelation demands a response, which always begins and ends with God's Divine purposes. "For it is God who is at work in us, both to will and to do, for His good pleasure. In this way, we can assure our hearts that, by God's grace and Spirit, we will be able to "serve the purpose of God in our generation."