Is it safe to say that you can't draw a conditional conclusion from a causal relationship?

For these group 4 indicators, I find it easier to go with the flow of the sentence (left to right) to be my sufficient and necessary (left to right) - so I always pick the second idea to negate and be the necessary condition first and "leave" the first idea on the left as the sufficient

For example: No holiday falls within the month of august.

I pick "within the month of august" to be the idea to negate.

I leave "holiday" alone in a sense - keeping it as my sufficient.

So -

Holiday --> /within the month of August.

It is easier for me to start here then flip things around and mess up the flow of the original sentence. I don't know if this is right of helpful but just how my brain works!

I wonder if it might be easier to start with the contrapositive with necessary condition indicators.