English 80 year old with French D Licence. Is it for life? B states 20/12/76 jusque 30/3/2008. Can he still?

My English husband is 80 with a a french driving licence. Is it true the licence is valid until 75 and he needs a medical every 2 years? We have a camper van with a "dolly" towing another car. Is he permitted to do this and on his licence Cat.E-B states "depuis le 20/10/76 jusqu'au 30/03/2008"? Does this mean he should not be towing?