"only XL-3"

Everyone who signs up for the tournament – on February 28th, we will finalize the list of participants and update the tables. The group tables will not be updated every hour as new players join, but only once every two weeks after the deadline for one round.

I would like a clear explanation of the rules regarding trading with different factions! I don't have much experience with this, and I haven't heard any specific suggestions yet: let's write it down clearly and concisely!