I started a new Survival World with the recent release of 1.14.1. After a couple of In-Game days I moved on close to a Taiga Village in a Mega Taiga Biome where I started to encounter with multiple Illager Patrols, they seem to commonly Pathfind close to my House since the Taiga Biome is just 50 blocks away, they come frequently from that side.
So focusing on this, after kill 5 Illager Patrols Captains I found a weird Pattern in these Patrols. First off I found close to my Spawn Point a Pillager Outpost, a couple of times I went close to that place resulting in lot of Pillagers following my back since they seem to have a very wide detection range. Now the problem is that this logic doesn't apply to a Pillager that spawns inside an Illager Patrol, being both Pillagers and Vindicators these 2 Mobs can detect me from a normal distance but they only focus on the Player without moving or show any sign of try to approach me, unlike the Behavior that you will find in a Pillager Outpost or a Woodland Mansion that in the exact moment they see a Player they start Pathfinding towards them.
Casually, it didn't took me a lot of time to find another Illager Patrol close to my Home and here I approached to take more time testing their AI
Trying to move around in different directions, they still focusing on me but there's no sign of try to get closer and attack me.
In this side the Pillager is very close to me and it's not even charging it's weapon, I can't tell how close I am, but from my guess I am like 11 Blocks away from it.
- I moved just 1 Block, see the Coordinate Z: 43 now
And this was enough to trigger the Pillager and make it get closer to 6 Blocks from me letting it approach me while is charging the Crossbow
But, there's another interesting observation that I found. Upon triggering their AI by getting very close they will remain the normal Behavior and will try to approach a Player like they were supposed to do in first place.
Here are some Screenshot from previous Patrols that shows this