Well you're stuck then.. So, what do you plan to do? Did you measure it independently, yourself.. ?
FWIW.. I Own a BridgeStone Road Bike.. it came with a 27.0 seat post,, marketplace has a lot of 27.2 seat posts..
Local Bike shop, in the off season, let me use an adjustable reamer, I carefully shaved out,
0.1 mm from the inside until a 27.2 seatpost slipped in.. then stopped cutting..
Now it fits perfectly ...
....