It does not appear that you can transfer your interest in one QOF for an interest in another QOF, without restarting your holding period, unless the transfer results from a merger of the two QOFs and the resulting QOF qualifies as a QOF after the merger. Treasury Regulations Sections 1.1400Z2(b)-1(c)(6)(ii)(C)(2) and -1(c)(10)(i) provide the relevant support for QOFs that are partnerships and corporations, respectively.