I got a closer look at that today since they removed the bottom of the siding above the deck. It looks like the ledger board is against the brick, but it's the same rounded broken surface as the rest of the bricks which offsets it from the ledger.

Anyway, it looks like they decided to replace the joists. I've heard that some of this composite deck surfacing requires joists that are closer together, so perhaps that's why.

The new joists are only 2x4s.

I looked up whether this makes any sense. What I found says that you can use 2x4s for joists, but only for decks near the ground and for spans of less than 5 feet and only if you space them 12 inches apart. These are spaced 12 inches apart but this deck is about 6ft off the ground and it's an 8 foot span. So perhaps that new beam I heard them talking about is to be 3 ft. from the house and 5 ft from the front? Just have to wait and see I guess.

They apparently have no intention of replacing the beams with anything more appropriate.

I suspect they'll be removing the old joists, so I don't think the new 2x4s are just for extra support, I think they'll be the only thing there when they're done. The new 2x4s are in groups of 3, and then there's a gap because an existing joist is where the 4th would go. If the plan were to keep the old joists then it would make more sense to center the new ones between the old ones, as there's already a new joist between each pair of old joists except for the very last pair at the end of the deck. So I expect that they're going to remove the old joists.

So new joists, new railings, new deck surface, and I also heard them talking about putting new footings for the posts. So the only thing they're going to keep are the beams (which makes them sound like more than they are, they're just the boards that the joists attach to) and the posts. If you're going to go that far, why not tear the whole thing down and just rebuild it properly, if nothing else just to not have the old ugly beams and posts on your otherwise completely new deck?