Pirates of the Burning Sea developers have posted the build notes for v1.11 called "Clash of Steel". There are a number of important changes so be sure to keep reading.

Content:

* Every AvCom mission in the game has been updated to work with the new system.
* We've increased the number of levels the difficulty slider adds to NPCs. This means each difficulty setting from the Port Captain should increase the difficulty of Avatar missions more than it used to.
* We've substantially changed the way boarding works. Instead of having 6 or 9 boarding members, you have 4 or 5. Boarding party members are also 1 level lower than their respective captains, and you have more waves of reinforcements than before.
* New group daily mission: The Guns of Del Morro! The Confrérie Libre have taken over an old fort overlooking a vital shipping lane and are sinking any ships that pass! You must fight through the enemy pirates, spike the cannons, and escape! Visit Santiago to try it out.
* New daily mission: Pit Fight! We've added a new daily mission in Tortuga that allows you to fight characters from every faction in the game, mano-a-mano. Completing the mission gives you a token that you can spend in a special shop with some new items and rewards. See Pit Boss Roy in Tortuga for more information.
* New solo mission: Bloodsport! This mission allows you to battle various factions in the game at no cost. Dying in the Bloodsport mission does not consume smelling salts, and there is no loot or XP awarded. This mission exists purely as a "Sandbox" for you to test out skills and combat. Visit your friendly neighborhood Fighting Master in Rosignol, Fort Caroline, Morgan's Bluff, Barilla, Belize, Biloxi, Spanish Town, Roseau, Golden Lake, Matthew Town, Maracaibo, and Santo Domingo.
* Old Fighting Master missions have been removed.
* Bey's Retreat and Fortaleza da Luz are temporarily hidden as we update them to work with the new system.
* Lots of bug fixes for encounters.

Skills and Outfitting:

* All player skills and effects have been replaced by new skills and effects. (See above for guides.) The new swashbuckling schools are separated into three skill trees: Control, Defense, and Offense. Gun skills are their own tree. These trees are 8 skills long, and the skills cost increasingly more points as you get closer to the final skill.
* Initiative now starts at 100, and regenerates constantly.
* Balance is now Guard, and regenerates at a slow pace. Your Guard represents your ability to avoid injuries, similar to the armor on your ship.
* Sprint is now a toggleable stance that you can use even while out of combat.
* All players and NPCs now gain stats at every level up.
* All NPC Factions have new skills, effects, and revised appearances.
* All weapons, armor and outfitting stats have been changed.
* Added basic outfitting to the Swashbuckling Trainer. You should now be able to get a piece of basic outfitting for every slot from 1-50.

Art:

* All new animations for Dirty Fighting, Fencing, and Florentine, as well as new Gun animations.
* All new NPC animations, including new Pistoliers and Musketeers.
* All new combat sounds, reaction sounds, and voices.

UI:

* You can now independently toggle Floating Combat Names for enemies, allies, and yourself. There are three individual key bindings in the preferences.
* AvCom tab targeting will no longer target enemies more than 30y away from you. No changes have been made to Ship Combat tab targeting.
* You can now only Ctrl+Click one skill at a time.
* Added new health/status bars for you and your target.
* Repurposed and redesigned the old balance circle to be a targeting circle. It now appears whenever you target someone.
* Added general buff, debuff and heal effects - blue for buffs, red for debuffs and green for healing.
* Added particle effects to indicate status effects, buffs, and debuffs.
* New sword trails and effects on all attacks.
* New grenade explosions.
* All new skill icons.
* Revised tooltips for the Character Sheet. They should explain more about the combat system than they did.
* Updated Avatar Quick Reference card.
* New loading screen tips.

...and tons of tweaks, bug fixes and improvements.

Be sure to head to the link above as there is a TON of guides and video tutorials to work through to make the v1.11 experience the best it can be!