Naval Combat Question

[SaintBio]

I just started playing again after a few years. I update the game and started a round as the Allies. I'm somewhat confused about 1 aspect that I do not remember in the old versions so I'm assuming it's something new. Essentially, when my naval units encounter an enemy naval unit there is always a 1-tile ring around the enemy unit immediately after the surprise encounter. None of my units can enter that 1-tile ring to engage the enemy ship. I looked at the manual but I didn't find anything. I made sure I wasn't running any mods, and I'm not. Does anyone want to explain this system?

[Nginear]

If you have enough movement points (APs) then it will have a shaded area with "Zoc" written, Zone of Control. It means you can move into the area but it cost extra AP....if you click your naval unit and the area around the enemy ship is completely blank, then you do not have enough APs to move next to that enemy naval unit with your current unit.

I believe the default ZoC penalty is +1 AP in vanilla, tho some mods have increased the penalty up to 10.

A naval unit's ZoC goes away if it's health is 4 or less.

[Elessar2]

Surprise encounters tend to eat up a ton of your AP, and that's before the ZoC penalty kicks in.

Note it is now possible to do separate ZoCs for land and sea units, and most modders have increased naval ZoC penalties.