From the photos, it is hard to tell whether it is normal mottling or more gray mottled than usual.
I suggest contacting the PB to make a record of your concern. But I also think it will be necessary to wait 1 to 2 months to see if the gray mottling discoloration gets worse.
See these posts for further information.
Gray (also spelled “grey”) or darkened blotchy or streaky discoloration of pool plaster (cement flatwork) is known to be caused by several improper plastering practices, including the addition of calcium chloride to the mix (even less than 2%), late hard or dry troweling, and sometimes a cement...
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One would think that when mixing white cement with white limestone aggregate, the final pool plaster product would always be white. But that is not always the case. Unfortunately, white pool plaster sometimes turns gray (or grey) either immediately or a few months after the pool is filled with...
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This experiment below explains how white pool plaster can become blotchy gray, and also have white areas mixed into the gray areas. Both white pool plaster coupons below have been in water for one year. Sometimes the water was slightly aggressive (negative CSI), and sometimes the water was...
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