The sooner the better. With the old self improver route to the airlines all but gone, the CAA/JAA must go back to the days of the FI rating being attached to a PPL. Even most pilots working for the airlines who had FI rating do not renew them (iam told that even 1 hours instructing invaladates a rest day). Most CPLs who had instructor ratings (not all) used it to help build hours toward an airline job, very few took there CPL/FI with the view of becoming a carreer instructor.
There are many good PPLs out there who would like to instruct, but are put off by the huge costs invovled. I myself have a PPL, IMC and a Class Rating Instructor (SE) Rating and just over 700 hours and would like to do and full FI rating, but now getting on the wrong side of 40 and not much hope of ever getting a commercial flying job (I know many CPL/IRs in their 20s finding it hard) I cannot afford or justify spending the best part of £26,000 on a CPL/FI.
