Any opinion grounded in experience developing long-lived software (as yours appears to be) is worth considering.
The downside of your specific approach is that (if the Perl PTB stick to their once-a-year release cycle), we need to go through compatibility checks (and fixing) once per year, as opposed to every other year if we jumped to the latest version instead. OTOH, in addition to net getting to get hurt by the latest and greatest bugs that come with the latest and greatest version (as you mentioned), the incompatibilities between 2 successive versions are likely easier to deal with than if jumping 2 versions.
no subject
The downside of your specific approach is that (if the Perl PTB stick to their once-a-year release cycle), we need to go through compatibility checks (and fixing) once per year, as opposed to every other year if we jumped to the latest version instead. OTOH, in addition to net getting to get hurt by the latest and greatest bugs that come with the latest and greatest version (as you mentioned), the incompatibilities between 2 successive versions are likely easier to deal with than if jumping 2 versions.