Is the ruling on dealing with savings accounts with variable returns in Bank Misr Haram or Halal, and what about the fate of past profits if the dealing was Haram?

If the branch of the bank where you deposit your money operates according to Islamic Sharia and is subject to Sharia supervision that ensures its transactions are free from usury, with accounts and profits independent from usurious funds and interest, then your money and profits are lawful. However, if it is not so, you must withdraw your money and search for an Islamic bank, and dispose of the usurious interest by spending it on charitable causes. We cannot identify specific Islamic banks in Egypt as we do not have this knowledge; you can ask trustworthy scholars there.