Understanding PPM Binary Package Availability - Why are some popular packages missing?

I'm using Posit Public Package Manager for faster R package installations, but I've noticed that binaries are unavailable for some surprisingly popular packages on Ubuntu 22.04/24.04 with recent R versions such as sf and glmnet. This also holds for various smaller CRAN packages. These fall back to source compilation, which is time-consuming.

Question: Is there a documented pattern or criteria for which packages get pre-compiled binaries?

Thanks for any insights!

Seems like this is a bug in PPM. From PPM devs:

Unfortunately this is a bug in how the PPM server handles binary installation requests, rather than missing binaries, so we can't fix this without a new PPM server release. Either that or CRAN allows Rcpp 1.1.0.8 to be fully released, which could actually happen within days.
The only workaround for now is to install from a frozen 2025-12-07 snapshot, e.g.:

https://p3m.dev/cran/__linux__/noble/2025-12-07

I am not sure what's going on with Rcpp. It seems that 1.1.0.8 was released, and then later removed.