Do you think that someone created the tunnel a very long time ago, or do you think that the RoR created it as soon as Neville got hungry?

And how did he get into a tunnel while being in a room starting on the 7th floor and else just rearranging all the time?

Did someone create the tunnel a very long time ago, or did the Room of Requirement create it as soon as Neville and co got hungry?

And how did he get into a tunnel while being in a room starting on the 5th floor or is it just rearranging all the time?