If it's for next year, it needs to be announced ASAP. Season tickets take time to sell and they won't want to found 5-8 new markets that will all lose massive amounts of money because there wasn't enough advertising time to drum up a fan base. On top of the massive amounts of money those franchises lost from breaking their current leases.
Several of the mentioned landing points have ECHL teams already in place, so they can quietly sell tickets for next year as they would be doing anyway (assuming that there isn't a price increase needed *worth noting that Western ECHL prices are pretty much in line with Eastern AHL prices*) in Ontario, Bakersfield, Stockton. You make a valid point for San Jose and San Diego, if they're indeed the other locations. It takes time to get staff in place, get sales calls going, etc. San Jose has a benefit of the big club already being in the community/having lists of hockey fans, so they have a pre-built call list and can advertise for it at the big club's games, if they want to, which could theoretically expedite the process there.
According to Patrick LaForge of the Oilers per the Bakersfield Californian, "The AHL and NHL are collaborating at looking at making some announcements at the end of January regarding relocations, playing fewer games with less travel and more divisional play"
I would guess that if there's a big announcement, the one at the end of January would be it.