Apologies in advance if this question has already been answered, but I can't find any information about this.

I was doing some searching at jetblue.com for flights from SFO-LGB with the new service, and noticed that B6 204 operates a morning departure through November 3rd when the 3 daily flights begin. Flight 204 continues on to JFK, so I'm assuming it has to be a A320, while I know that SFO-LGB will normally be operated with a E190.

The other flight currently on the route carries the flight number 1436, and it appears that after 11/3 all of the flight numbers are in the format 1xxx. My question is do the flight numbers here correspond to aircraft type (ie, does a 1xxx flight number always mean an E190?) or is this just a coincidence related to the start of SFO-LGB service?

Thanks!