So I get told the location, course and speed of a convoy over 800 nautical miles away. I plot my intercept (Thanks XLJedi

) and get to within a few miles away.
I'm using the no spoilers mod so effectively map contacts are off. I close to visual range and start plotting out their tracks, trying to spot where the escorts are and the juciest targets. I shadow them for 2 hours waiting for night where I will enact my meticulously hatched plan.
Checking back I notice a course change. Ok it happens, might be actually helpful.
Chaos ensues. To highlight this I changed the datasheet of the no spoilers mod to re-enable map contacts.
This isnt the first time either. Most commonly it happens when a convoy is following a coastline, this is the first time ive seen it happen mid ocean.
Any of you experiancing this?