There are 3 threads, where fpga devs are selling(or incite to buy) this devices today.
Most of those algos were FPGA and ASIC resistant in past(like scrypt, x11,x13, quark, etc). But coin devs trying to make fpga-resistant and asic resistant algos. They will increase memory size and bandwidth requirements and make new resistant(today resistant, not tomorrow) algos, like mtp, equihash(with different parameters), phi2, etc.
So, we wait for the next chip and launch then

-- Once the stratix and virtex devices with HBM2 hit the market, there's nothing that the coin devs will be able to do. Literally, nothing.
You sure about that? With ProgPoW having to make FPGA's replicate a GPU, it will erase benefits of specialization, and as such will make a GPU more cost-efficient as they have economies of scale at their side.