def, what are the odds that SSF will still be tradable at IB next year? AFAIK, no other broker offers it for US stocks, but it does exactly what I need to scale up the strategy once I reach portfolio margin. However, that doesn't work if the product is not available to roll contracts, or if they won't trade near fair value. Even if SSFs are not listed in TWS anymore, will it still be possible to perform block trades perhaps using a third party? How large would the size need to be? (I know you probably don't have the answer right now)
There is no way to replicate these futures using options (ie, short synthetics) because NLY is a high dividend REIT - early exercise risk means having to constantly adjust options as opposed to just rolling a futures contract that has no dividend exposure; add time decay and spreads in as well as opposed to actually earning a bit of interest - this product does fulfill a specific need.