If you have a finite-horizon value function with N_j periods, you can pass a ‘period N_j+1 value fn’ using vfoptions.V_Jplus1.
For example, say you are evaluating policies that only impact working ages, so the retirement periods value fns are unaffected. You could solve the model once using working+retirement periods, then put the first retirement period as vfoptions.V_Jplus1 and from then on only re-solve the working age periods while evaluating different policies. The purpose of all this being to reduce runtimes.
The vfoptions.V_Jplus1 has now been fully implemented and tested across all the FHorz test banks, so can now be relied upon 
[Has not yet been implemented for use with FHorz TPath.]