[theory] How does a boost converter behave when it receives input voltage above the target output voltage?

What is the boost converter doing when it receives input voltage above the target output voltage?

I have a homemade TV remote that I designed with a NCP1402 boost converter so I could power with a single AA and have a 3.3V board voltage. Worked fine in testing, but I wanted more range. So I swapped out the standard 1.5 volt alkaline AA for a 3.7 volt 14500 Li-Ion. The board components can handle the extra voltage. Not worried there. I was curious what the boost converter thinks about the situation.

Example schematic:

Datasheet: https://www.onsemi.com/pub/Collateral/NCP1402-D.PDF

My observations and theory: When I input 3.7 volts and probe the boost converter’s normally 3.3V output, I see the 3.7V input voltage instead. Using block diagram in the datasheet, I imagine the boost converter gets stuck in a voltage feedback loop. Never engaging the oscillator.

See reddit for responses.

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