I believe that, for R, releases are synonymous with distributions. The code is compiled on the user's machine (I once had a fortran error message while installing an R package).

If reproducibility matters, you can also use Microsoft R Open to get your packages from a frozen snapshot of CRAN : https://mran.microsoft.com/

R / CRAN provides precompiled distributions for macOS and windows machines, but builds those distributions on its own infrastructure so they’re available more-or-less the same time the source distribution is. Additionally, R/CRAN do not try to solve the problem of binary releases on Linux distros, and instead default to source distributions or defer to the OS package manager