Many Golani soldiers reported this:
A few hamas terrorists were captured and interrogated . We asked them, "if you had these tunnels for so long, how come they were never used to kidnap or kill Israelis?" They answered: "we were digging and building for 2 years. Many tunnels ran 25 feet below the surface all the way into Israel. We prepared for 2 years and were ready to use them this Rosh Hashanah.
The plan was to attack with 125-130 terrorists in each tunnel (40 found so far), armed and dressed as IDF soldiers. On Rosh Hashanah, we were to set off explosions and kill as many Jews as possible. That is when most guards are off in shul for the 2 day holiday.
"We planed to kidnap as many Jews possible, and hide them in Gaza as human shields. It would have been the end of israel, we would have taken over." All of the Hamas terrorists were going in, and they were almost ready--only 2 months left!
This Rosh Hashana they were going to do this! And our war now saved our lives."
The tragic deaths of the three boys kidnapped enabled the IDF to find these tunnels before mass destruction took place.