Is a banking entry considered a constructive possession sufficient for the validity of exchange in currency trading using the margin system, especially when selling the currency before settlement to avoid the rollover fee?

The resolution of the Islamic Fiqh Academy states that the banking entry of an amount into a client's account is considered a constructive possession, recognized both by Sharia (definition) and custom, in cases including: direct deposit of an amount or via transfer, a spot exchange contract between the client and the bank, and the bank's deduction of an amount from one account to another upon the client's order. A delay in the banking entry for customary periods is excusable, provided that the beneficiary does not dispose of the currency during this period except after the effect of the banking entry allows for actual receipt. Selling during this excusable period is not valid; rather, it is necessary for the currency to be available for withdrawal and disposal. Selling the currency before settlement (delay in actual receipt) is not permissible, and overnight fees are usurious interest. Furthermore, investment in currency speculation (Forex) is one of the most dangerous types of investment due to extreme price volatility and the reliance of speculation on guesswork and risk-taking. Therefore, it is safer for a person to avoid it.