I had a shell breakage with a pair of Unique Melody CIEMs, a few years ago. To be fair to UM, I must say that a work colleague sat on my jacket, and they were in the jacket pocket (I did honestly admit this to UM). That is excessive force.
However, as it turned out, the shells actually
were much thinner than they should've been (and it was admitted to me, by their agent, that several of their customers had experienced the same issue, during that time period). This time period of manufacture was during the Global Promotion they had at the time.
I strongly suspect that they had one or more technicians on the team who may have been rushing their workload by not exposing the liquid acrylic to UV light for enough seconds per batch. It may even have been a newer member of the team, recently employed in order to help the company keep up with sudden demand (the Global Promotion marked UM's first major push into the international market).
I can't comment upon the reason for any incidences of EE shells perhaps not being as thick as one might prefer, but there appear to be interesting parallels, in terms of rapid expansion of the company.
In any case, UM were as good as gold and dealt with the re-shell efficiently and without charge.
I'm sure EE will handle any such re-shells with equal grace.
For anyone not familiar with the UV method of CIEM manufacture, explanatory videos can be found within this post:
www.head-fi.org/threads/things-to-consider-before-getting-your-custom-iem-impressions-done-the-perfect-fit.578855/#post-7871678