What are legal risks during probation and appeal in IPC 392?

I was convicted under IPC 392 and granted two years' probation by the lower court. What happens if I am accused of a completely different charge while still on probation—even if the new case is unrelated or not even criminal in nature? If I file an appeal with the Sessions Court, can they increase the punishment upon conviction? What is the maximum number of years this case can be delayed or stretched in the Sessions Court for a final decision? What happens if it is later found that the witness (panch) has a serious criminal record that was not disclosed to the lower court, but is presented before the Sessions Court? Are there still any chances to apply for travel visas during or after such proceedings? If the Sessions Court convicts me, what legal options do I have? Can I appeal to the High Court after that?