As of 15 minutes ago, I've put icenReg v1.3.5 on CRAN (and as always, a thanks to the core R team for keeping that running!). Some changes from last time:
Inclusion of the parametric accelerated failure time model (AFT)
Sped up ic_sp after recognizing a minor bug
Added a vignette explaining what interval censoring is, the models fit by icenReg and walking through some toy examples
That last change is, honestly, the largest contribution to the package. In the real world, it's not really that helpful to calculate various estimators really fast if no one knows what they are estimating.