120 grit is good. The reactive stain is water soluble. After applying the reactive stain, the pores will open up, allowing oil to penetrate deep. Rubio is a film-forming oil. If, the proper coverage is applied the fibers will be filled and you will have a properly performing finish.
The only issue that I can think of is the contractor's application method. The contractor must have buffed in/out the oil, instead of troweling. This method doesn't allow enough time for the finish to soak in the fibers. There is a 10-15 minute soak-in time, before polishing it. Not only that, the pad will hold most of the oil, so you really have to work the oil into the wood fibers with a buffing pad. Not doing so, you will miss out on proper coverage. Ending up with an under performing finish. It can be done, but requires time. With 2500 sq. ft., the contractor was ambitious to complete the project.
Best method for oil application is to trowel-in, 10-15 minute wait, equalize with a red pad and then polish with a white pad for oil finishes. Troweling the oil will force oil deep into the pores, ensuring proper coverage, compared to buffing. Very effective for textured or uneven floors. It also, allows the finish time to soak into the fibers, from the start point to the end point of troweling, usually 150-200 sq. ft., before equalizing.
Anyways with improper coverage, any liquid spilled will reactivate the reactive stain and move it around or dissolve it. Which is, what is happening in your photos.
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Winner: MMAD ArchitectureWho can resist charcoal-toned tiles laid in a herringbone pattern? When they sweep along the floor and climb the shower wall the tiles become even more of a feature.
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