As people have been opening some of the advanced headers, some have been sharing their new skill descriptions on the #portkatherine channel of the boston-larp slack. (Did you know there was a slack channel for Port Katherine? Now you do!)
They agreed to let me share them here, as well. No pressure if you want to keep yours secret so you can surprise us, but if you want to brag, well, here’s your chance. 
EXPERIMENTER (Advanced Apothecary):
3 Component Chemistry (5): You may combine 3 items (components or vials) with 1 arcanum during BGS to create 1 elixir. No elixir may have more than 8 properties total - if the ingredients together contain more than 8 properties, extra properties will be removed randomly.
Mixology (5):* You may add a vial to any elixir you create without it counting towards the total number of items in the elixir (i.e. you may use 2-component chemistry to create an elixir with 2 components and a vial, or a component and 2 vials, or 3 vials)
Theoretical Chemistry (1): You can submit a combination of properties in BGS to see what effect they will have without expending components or vials. Each submission costs 1 point per common property, 2 points per rare property, and 3 points per ultra-rare property in the proposed recipe.
Equipment Expertise (4):* When creating a known elixir, you can choose what form factor the result will take (potion, oil, perfume, or powder). There is no guarantee that the new form “works.”
PHYSICIAN (Advanced Surgeon):
Miracle Worker (5): In a hospital, you may spend a use of this skill, plus a use of Awaken, to reduce the time it takes you to perform a Surgery to instantaneous.
*Elite Surgery (4): When performing Surgery, you now place a white bead and a black bead in the subject’s surgery bag if performing surgery in the hospital. (Field surgery is unaffected by this skill)
*Post-Operative Care (4): Your patients’ recovery time during which they may not use any skills after surgery now only lasts 10 minutes. Inform them of this after you complete the surgery.
*Operating Theatre (2): Spend 1 minute setting up your medical equipment and operating space in the hospital. Once this is complete, as long as you remain inside the hospital, your natural Healing skills are tripled.
GADGETEER (Advanced Engineer):
Craft Advanced Engineering Schematic (5): If you have an Advanced Engineering Schematic and the requisite materials, you may craft the item shown in the schematic during BGS. Schematics are not consumed by this process, but materials are. Additional purchases of this skill allow you to craft multiple items, as long as you have the requisite materials and schematic(s).
*Junk Drawer (4): When you purchase this skill, select one type of part. You are considered to have as many of these as you need, from spare parts lying around.
Recycle (3): For each purchase of this skill, you may take an existing item created with Craft Engineering Schematic (of any level) in BGS and turn it into one of the parts required to make it. If you also spend your Focus, you receive all of the parts used in its construction.
*Invention (3): You may invent new Advanced Engineering Schematics.
POLYMATH (Advanced Scholar):
Practical Application (5):* You may freely use purchases of Research as Experimentation, and vice versa.
I Read it in a Book! (2): The first time you use this skill in a given day, choose a 1 or 2-CP non-True skill from another rulebook header for it to mimic. For the rest of the day, uses of this skill acts exactly like uses of that skill (if you select a checkbox skill, then you gain infinite uses as normal, though additional purchases of this skill are then “wasted”). You may change skills that it mimics on subsequent days, but spent uses are not recovered, and refresh is treated at the CP cost of this skill and not the duplicated skill. You may not use this skill to mimic BGS skills.
Translator (2): You may spend a use of this skill to immediately read a document in Tiyagan or Onzekkan (choose one when you first take the skill). You may learn to translate any other human language by spending 10 Research studying a comprehensive sample of that language.
*Everything is Connected (4): Once per event, you may substitute this skill for any mechanic that requires a specific header or ability (i.e. a tag that requires a use of Pierce, a machine that needs an Artificer to operate it, etc).