According to @ChrisR's thorough answer
One caveat however is that the interpolation in DE438 is a Hermite interpolation, and no longer a Chebychev interpolation, so you may need to update your code.
The JPL Development Ephemerides have been around in some form since the 1960's. If I understand correctly, these as well as the "Spice Kernels" (no, not an all-male version of the Spice Girls) usually if not (until recently) always have contained coefficients for Chebychev polynomial interpolation to produce continuous state vectors; trajectories for bodies and objects in space.
Question: Why would DE438 be released using a different class of polynomials (Hermite) for its interpolation?
fyi #1: I've tried Skyfield using
data = load('de438.bsp') and it seems to work, so perhaps at least some existing ephemeride readers are already compatible with both?
fyi #2: according to this answer :
(ephemerides is) pronounced ɛfɪˈmɛrɪdiːz/ ("effih-MERRih-deez", which for some speakers is the same as "effuh-MERRuh-deez").