Roster and match concepts
Rosters, slots, signup states, and what the event log is.
A roster is a grid of slots (role plus class per slot) for one GvG lineup. Create it on the Rosters page from a template or with custom slots, then announce it to a Discord channel: members use the Sign-up and Withdraw buttons on the embed, and the embed updates live. Premium guilds also get the class select menu on the embed.
Officers manage the same roster from the web editor: drag a member onto a slot, double-click a name to auto-fill, clear a slot, or set attendance states. One roster can be duplicated for the next match instead of rebuilt.
The event log (Events page) is the operational audit trail: match starts/stops, settings changes, roster actions and guild joins/leaves. It is a log feed, not a calendar; the public read-only calendar view lives under /calendar/<guild_id>.