The Federal Housing Finance Agency is expected to announce lower GSE loan limits by October, a move that should provide a further boost to the jumbo mortgage-backed securities market, according to housing lobbyists and other industry observers tracking the issue. However, it’s unclear how much of a reduction to the current cap of $625,500 might occur.“I think everyone in the business is anticipating this and getting ready for it,” said one mortgage insurance source. A housing lobbyist added that, “Right now it’s a matter of timing. Will it come in October or a little later than that?”