Using MIG in OOC non-project mode

Question

We're trying to use the MIG with Vivado v2015.2 in an OOC non-project workflow for a Kintex Ultrascale device.
However trying to build the MIG itself out-of-context fails at opt_design stage with an error that MIG configuration is incomplete.
Putting the MIG in the top-level design means that as soon as a routed design checkpoint is loaded, building fails with 
ERROR: [Mig 66-106] The MIG I/O ports have been moved since the last time the design was implemented. Due to a current limitation, Vivado cannot execute opt_design in this situation. In order to proceed with the current task, you must first save and close the current design in memory. The flow must be restarted with a synthesized design by either loading the synthesized design checkpoint or re-running synthesis.
I've tried all sorts of stuff, read_checkpoint+synth_design, or creating a synthesized design with black boxes and then add_files & link_design but in the end the only way to avoid this issue seems to give up on OOC implementation altogether.
Are there any known workarounds for these issues?

Answer 1

BTW, it works fine in Tomcat 6,7........