TXV bypass

I'm trying to understand a packaged heat pump TXV. I understand that in heat flow refrigerant bypasses the orifice part of the TXV flowing in reverse. Some specific TXV documentation indicates that the TXV has a check valve. If a TXV has a check valve is the reverse bypass always internal in the TXV? It's hard to see in the cutaway diagrams of the Sporlan TXVs where a reverse path might be. Maybe that's just not pictured.

source https://hvac-talk.com/vbb/showthread.php?2226791-TXV-bypass&goto=newpost