Update: EA has revised the blog post, which contained outdated information, to say now that Grand Operations will be available at launch. The original story below is thus outdated.
Original story: EA posted a refresher on Battlefield 5's multiplayer modes (correction: this was posted last month, not recently), beginning with its replacement for BF1's multi-match Operations mode. Grand Operations will see teams battle over multiple in-game 'days' through different modes including Airborne (one team jumps out of planes) and the respawnless Final Stand. But not right away. According to the post, Grand Operations is coming 'shortly after launch.'
The other mode that won't be available at launch is the battle royale mode, which got just a moment of stage time at E3. I would expect there to be a decent wait for that one (especially given that DICE didn't even have a logo to show), but Grand Operations has already been played at preview events, so I'd wager that 'shortly' really means shortly in this case. I'm speculating, but DICE will probably roll it out sometime after the initial launch rush, give or take any time required to smooth out issues.
I like the Operations and Grand Operations modes in principle, but I'm always more excited to play regular old Conquest when a new Battlefield launches. I found BF1's version of Conquest to be flawed for a few reasons, so I'm pleased that BF5 has scrapped behemoths and the new scoring system in favor of more classic rules.
For more on that thought, here are some of the improvements over BF1 we found in the first Battlefield 5 alpha. There'll be an open beta in September so you can try it for yourself, and Battlefield 5 will launch on October 19, or about a week earlier if you're an Origin Access member.