Too close to 5-year reinvestigation date to transfer sponsorship?

Hi, everyone. I’m a full-time contractor who has a TJO for a full-time permanent Federal position that requires a Tier 2 MRPT, which is the same level/Tier that I have with my current agency. Unfortunately, OPM has let me know today that because my current Tier 2 is coming up on the 5-year mark in May, it is too close to the reinvestigation time to simply transfer the sponsorship of it and I am going to have to go through the reinvestigation process. I have nothing to worry about as far as the investigation itself goes, but I am frustrated that this is going to now push back the start date of my new job.

Do I have any other options here, or am I just at their mercy? Thanks for your time.