Good morning Andros,
UV light defines the wavelength spectrum of the light source while LED defines the type of the light source. You can have a UV regular lamp or a UV LED lamp etc. The difference between the two is the power of the light source since LED is in most cases weaker.
Since you are already a customer of EnvisionTEC i would suggest creating a ticket and requesting the cookbook for EPIC resin, in which case EnvisionTEC will provide a PDF document with all the steps, burnout cycles, post curing times. I think this will help you get better casting results.
To provide some additional info until you have the cookbook at hand, EnvisionTEC recommends removing supports before postcure, preferably with a friction disc which makes it easier and less likely to break something of, although i myself,on castable resins postcure the parts a bit before removing supports so they are harder and then complete the post curing process.
If you are using Otoflash G171 the recommended process is 10000 flashes in total. 2000 flashes a time, with 2 min cooldown with closed flap and if possible you turn the part every time for a total of 5 times.
If you are using the Cobra LED PCU its a total of 18 minutes. 9 minutes at a time, with 2 min cooldown with closed flap and if possible you turn the part every time for a total of 2 times. While Otoflash flashes, the Cobra LED PCU has continuous light.
For more detailed information just request the cookbook from support and once you receive it, it includes diagrams and complete step by step guide on post processing once your part has finished printing.
Hope this helps.