One workaround is to execute and live trade Put BFs but input the trade manually into ONE as an Iron BF. They are synthetically the same thing. This should solve the margin issue. You can then manage the trade using the Greeks as per updated guidelines for ONE.
Synthetic equivalents meaning they are all the same Risk and Reward and thus effectively no different >>
A Call BF, Put BF and Iron BF with same widths and strikes…whether they are credit or debits is of no concern except to some brokers who do not understand this concept or have blanket margin rules.