Just got the comic on comixology. The supernova happens between 2385-2386. The 2387 date from Trek 2009 seems officially dead and likely has been retconned as a stardate rather than a proper Earth year. Picard has been mobilizing a fleet and working under the Federation with the Romulans for years, literally, using the fleet to evacuate Romulan space (not just Romulus itself but Romulan space planets threatened by supernova). Picard is on the USS Verity as Admiral during this time. Geordi is in Starfleet as a Commander and isn't a private engineer like the old non-canon Countdown comic. Riker and Troi are still mentioned as being on the Titan as of 2385. Nothing like the old Countdown comic with a last minute notice on the supernova before it happens. It's completely unclear why Nero would blame Spock and the Federation if they were helping the Romulans for that long. There is the issue where Picard refuses to evacuate a colony because the Romulans won't bother with also evacuating the enslaved native species there, but it's not clear this has anything to do with Nero (who made it clear in the 2009 film he's from Romulus itself).