Ed Mullen has implemented a website to extract limb darkening parameters for the CBB filter from new limb darkening data tabulated in Claret et al. 2022. The CBB filter is a useful alternative to improve photometric precision for smaller telescopes compared to using typical Sloan or BVRI filters, but at the expense of loss of transit depth chromaticity information (which may or may not be important for your observation). The filter can also be an alternative to the no-filter/clear filter option since it blocks bluer wavelengths and thus may reduce airmass trend in your light curves.
The limb darkening coefficient website can be accessed here:
www.cbbldc.comWe at AIJ do not provide a specific recommendation for the CBB filter, but if you are interested, they are available here:
https://farpointastro.com/products/astrodon-exoplanet-light-curve-filtersKaren