I've seen a lot of Eternabond do that. My "hunch" (and I have no way to prove it) is the solvents used in the adhesive on the tape. Just like the "hi-voc DICOR sealant" there is enough solvent in the tape adhesive to "temporarily liquify parts of the TPO membrane. When that happens, wrinkles appear.
DICOR and Alpha Systems developed "lo-voc sealant" with minimal dispersal solvent to eliminate the chemical reactions with the TPO membrane....
We never had that kind of issue with EPDM roofing from the sealant or from using Eternabond tape.... That's no longer true with the TPO membrane... I don't have much exposure to the new "PVC roof" material, so I wouldn't predict whether we'll have newly blended sealants to use with it in a year or two...
As for your roof, I'd watch it, not panic and if it continues to get worse, contact Eternabond with photos. They may have some ideas on how to reduce further wrinkling... Then again, they may just shrug their shoulders and recommend "watching it and not to panic"....