In cases where a the basics are unchanged, but there are new developments, how about augmenting old eps with addenda? So for instance, ep 51 would become ep 51.01 with supplemental material tacked at the end. And maybe in cases where the subject has been revisited in a later episode, a small note at the beginning of the older one pointing listeners to the update.
Sounds like a lot of extra work, no?
Meet the drop-resistant Moto Z2 Force
The Moto Z2 Force is really thin, with a fast processor and great battery life. It can survive drops without shattering.