I believe that the apostles were dispensational in the way that they viewed the Scriptures. To them it was simple. The Messiah had come, and as per the Old Testament prophecies, he was going to restore the kingdom, and fulfill the Davidic and Abrahamic Covenants just as God had promised. No, they did not see the cross. This is evidenced both by their increased questioning as to who would be the greatest in the kingdom and Peter's rebuke of Christ for even suggesting his purpose for returning to Jerusalem. Eventually, the cross came and they were demoralized, but after the resurrection, and some obvious clarification laid out by Christ during the forty days before his ascension (Acts 1:9), they were re-energized because the purpose of the cross had apparently been made clear. Moving forward, their focus stayed the same in that they were still looking for the restoration of the promised kingdom (Acts 1:6). This is evidenced by the fact that their message never changed. It still remained as it was in the Gospels; repent and be baptized (Acts 2:37-38).
Sadly, their message was ultimately rejected by the nation of Israel and God raised up the Apostle Paul to start what would become the church age (Acts 9). Yes, initially, Paul did preach the same Kingdom Gospel that the apostles preached, however, at some point between his departure and return to Jerusalem fourteen years later (Galatians 2:1), the mystery of the church had been revealed to him and he was now preaching a different gospel: the Gospel of Grace. No doubt, Peter and the others, realized that something was changing, e.g., Cornelius (Acts 10:1; Acts 15:7), but did not fully understand it until the Counsel in Jerusalem (Acts 15) when Paul returned and explained it more thoroughly. It was at that point that Paul's gospel was confirmed by the twelve (Galatians 2:2) and they parted: the twelve still remained with the Jews in Jerusalem still looking for the kingdom and preaching the Kingdom Gospel and Paul went to the Gentiles preaching the Grace Gospel. They are not the same. The first is still under the Law and the other is under the new dispensation of grace.
It must be understood that the timeline never changed for the apostles. As per Daniel's prophecy and many others in the Old Testament, their expectation and hope were that Israel would eventually repent nationally, the Tribulation (Daniel's Seventieth Week) (Daniel 9:24; Matthew 24:15) would commence, and would culminate with the Christ's Second Coming, the establishment of the kingdom, and them sitting on twelve thrones judging the twelve tribes of Israel just as they were promised (Matthew 19:28). This is reflected in all of their writings without exception. This apparently remained a hope until the eventual destruction of Jerusalem in 70 AD and the death of John, the last apostle. One would do well to remember this when they are reading anything between James and Jude in the Hebrew Epistles of the New Testament. They were always addressing the believing Jews and preparing them for the tribulation that they fully expected would come. Paul, on the other hand, had turned to the Gentile and the establishment of the church: the Body of Christ. As such, the apostles were teaching the Gospel of the Kingdom that required repentance and baptism, while Paul was teaching the Gospel of Grace that required only belief in the death, burial, and resurrection of Christ. Failure to see this transition is the reason for so much confusion in the church today, e.g., baptismal regeneration, amillennialism, postmillennialism, Preterism, Replacement Theology, much of the Pentecostal movement, the loss of salvation, etc. In my opinion, it is only through the lens of the dispensational view that this can be seen clearly.
Unfortunately, it is clear from the writings of Paul that most of the churches that he had founded or mentored eventually turned away from the Gospel of Grace that he preached and placed themselves back under the Law or Gospel of the Kingdom (Galatians 1:6) and have quite frankly done so ever since, e.g., finding the church in the Gospels and the other writings of the apostles. With that in mind and the fact that the kingdom never came, in their ignorance, following the writings of Augustine, they began to spiritualize and allegorize the texts to make it say what they wanted it to say. As a result, the church became Israel, they were now living in the kingdom, the pope became the vicar of Christ on earth, and Rome became the Holy City, i.e., amillennialism. The Protestant Reformation did little to change this theology other than to reject the authority of the pope and gravitate from amillennialism to postmillennialism. Neither interpreted the Bible literally and both led to preterism. Dispensationalism was not lost but purposefully left.
It would not be until Jonathan Edwards and Charles Finney on the edge of the Second Great Awakening that progressive revelation was revisited, wrongly so, as they waited for the kingdom that would apparently begin in America as a result of Joel 2 and Acts 2 being fulfilled. Yes, America was going to be that great "city on a hill" (Matthew 5:14) that they were waiting for. Unfortunately, the reality of the Civil War shattered any thoughts of that happening anytime soon.
Dispensationalism did not come full circle again until a fellow by the name of John Nelson Darby of the Plymouth Brethren in Great Britain began what would come to be called The Dispensational Era. Darby's teaching was popularized in the United States by Cyrus Ingerson Scofield via the Scofield Study Bible and the subsequent rise of fundamentalism between 1857 to around 1956 which sadly came to an end with the advent of Evangelicalism which is another topic for another day. The bottom line is that Dispensationalism is not some new contrived invention as some would suggest. We are merely returning to a literal interpretation of Scripture.