My wife and I were sitting in a cab on the (long) drive back to OC from LAX listening to the initial NTSB presser. While the spokesperson mentioned the normal investigative timeline, she did mention that they and/or the USCG could issue an immediate bulletin if warranted.
At the time I speculated findings would be related to Li batteries. Li has been long known to be a volatile, which is why the re-charging control circuits can be compromised if sourced from non-reliable labs (China).
My sister is currently living in south China, and she said that while airport security can be lax about liquids, the Chinese are super focused on smart devices and re-charger units. From what she mentioned, all of that gear attracts a lot of scrutiny.
As an aside, my wife told me someone on a travel forum who is currently on a cruise ship said that new instructions during the safety review included not leaving any charging devices untended. So, it looks like this bulletin is going to have an immediate and broad roll forward effect on all sea borne vessels.