Availability of sub-compact chainrings?

[Clancy]

I believe I saw a while back where a company is making sub-compact chainrings that will bolt up to a Shimano compact crank. I believe there was an option of 32/48 and 30/46 and that the company was able to design them to bolt up with I believe some type of different chainring bolts.

Is anyone aware of such a product?

I mounted a White Industries sub-compact crank on my gravel bike and love it. Would like to experiment with different chain rings on the road bike but not at the expense of another crankset.