When does a unit go "under" an entrenchment?

[saracv3]

I used Direct Fire (First Fire) on the SA troops when they came ‘over the top.’ In contradistinction to the previously ineffectual adjacent DF which fell on the 16 column.

You don't get to opportunity fire on units as they move into an assault hex. "First Fire" is always assault fire.

I didn’t think I got OP Fire, I thought First Fire was resolved on theDF table. After rereading 12.43 I realized FF is resolved on the Assault table. I should say that it seems logical to resolve FF on the DF table and I gave a +2 shift to the shot, not a +3, which might happen in the hex before entrenchment hex.

I am not trying to be an annoying rules lawyer, but the PG rules forum seems like a good place to get these questions answered and observations discussed.I guess I should not have added a narrative into the discussion.

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