I have heard or read (though I cannot recall where) that a sotapanna anugamu will definitely attain sotapanna pala before his death in that very same life time. If someone has a tripitaka reference for this would be great if you can share it.
The only similar reference I have found is in the Puggala pragnapthi dathu katha, where two types of individuals are mentioned; shaddanusari and dhammanusari. Both are working towards attaining sotapanna pala. The former will attain sotapanna pala as shadda being the forerunner while for the latter pragna will be the forerunner.