These are not based on actual futures. From IG Support:
FTSE 350 markets are based on FTSE100 and FTSE 250 indices. They take the market cap of each component and derive an index for each industry.
But they do offer DFB as well as dated bets (for carry), and the epics look like they may follow the FX model of having MAR, JUN, SEP, DEC periods. If we could get prices without hitting the rate limits, it might be worth getting them sampling
IG offer dated FTSE 350 sector bets, eg
These are not based on actual futures. From IG Support:
But they do offer DFB as well as dated bets (for carry), and the epics look like they may follow the FX model of having MAR, JUN, SEP, DEC periods. If we could get prices without hitting the rate limits, it might be worth getting them sampling