@Trenor Thought of you when I posted this one. Off a smartphone, not the high res of a DSLR. S/he has increased the trapdoor height on the left slop as it molted a few weeks ago. You can see the top of another trapdoor at the back right barely. It's one long tube/cave. What can't be observed is another trapdoor that extends beyond towards the back left corner, less used.