From I am reading is that there is still some back-and-forth from all the decision-makers/stakeholders. However, it points to the conclusion that TXL will be closed for pax traffic in early Summer.
It would be quite interested to see BA and LH operating from the old Socialist terminal at Schönefeld. Since it looks like that each passenger will have to wear a mask, I'd assume the number of flights will be increasing by the end of this summer. It may get busy at the very small SXF.