From Raid Leader Zextol:

We will be holding a mandatory pre BFA raid meeting on 8/23/18 (see the guild calendar to sign up). All raiders/new guild members seeking to raid Uldir please make it a point to attend; the event starts at 4:00p server (7:00p Eastern). We will be discussing weekly progression times, rules and requirements, establishing roles and just overall tips for preparing for the first week of Uldir. Speak to a raid leader if you will not be able to catch the meeting and we will do our best to accommodate you. We look forward to seeing you all!!