In the Journal of Apicultural research (JAR) the following was published in March this year. I don't have access to the full 'paper. However what is interesting is that the abstract would imply that new comb is better than old and that a 3 year cycle of comb replacement does make sense. Maybe I need to get rid of my "vintage" comb after all!
"Abstract
A study was carried out to investigate the influence of differently aged wax combs (foundation as zero, 1, 2, 3 and 4 − 6 years old) on some biological aspects that affect the productivity of honey bee colonies. Twenty-five package colonies were equally divided and situated on each of the tested combs during the spring of two successive years (2018 and 2019). The obtained results revealed that worker brood areas, worker population, worker life span, weights of newly emerged workers and drones, and honey yield significantly increased with fresh combs. However, drone brood areas increased with old combs, and wax combs age had no effect on worker survivorship. It could be concluded that the wax combs aged from zero (foundation) to three years old (light color combs) are more preferable in the performance and productivity of honey bee colonies than the older (dark color combs) ones".
"Abstract
A study was carried out to investigate the influence of differently aged wax combs (foundation as zero, 1, 2, 3 and 4 − 6 years old) on some biological aspects that affect the productivity of honey bee colonies. Twenty-five package colonies were equally divided and situated on each of the tested combs during the spring of two successive years (2018 and 2019). The obtained results revealed that worker brood areas, worker population, worker life span, weights of newly emerged workers and drones, and honey yield significantly increased with fresh combs. However, drone brood areas increased with old combs, and wax combs age had no effect on worker survivorship. It could be concluded that the wax combs aged from zero (foundation) to three years old (light color combs) are more preferable in the performance and productivity of honey bee colonies than the older (dark color combs) ones".
May your bees read the same books as you do.