Can a PDA guess more than once? L = {aⁿ bⁱ aⁿ | i,n > 0 } PDA = Pushdown Automata

Let's assume I have this language:

$L = \{a^nb^ma^n | m,n \ge 1\}$

Would the first approach with one node be enough - in that case it guess twice the $\lambda$. In the second approach it's deterministic, which is fine.
Here is a solution with one stack. 


Start inserting a's into the stack.
Stop inserting a's when we encounter the first b. Halt any operations with respect to the stack as long as we get b's.
Start popping stack contents immediately when the b's stop and a's start.