It's possible to go to the past and meet your past self. After doing it, it will take the amount of time you traveled to the past for Time Bastard to eliminate the past self.
For the Frog example, he goes back two years, and can meet his past self. Two years later, and the past self will get Time Bastarded, as it was the time the original Frog time traveled.
Now, depending on the situation, the impact on the new time line created by your time travel depends on what you did. It can be a small change like just having a little talk, or something big like making him do a differnet desicion of what you did.
Depending on the situation I would advise not doing the latter.