The helium shell is occupied by 2 electrons with anti-parallel magnetic dipoles (so far spin up and spin down).
In the neon shell, the 8 electrons are arranged on the edges of an imaginary cube, always alternating with the north or south pole facing the nucleus.
In the series of atoms from lithium to neon, the mutual influence of the magnetic moments gives rise to the sawtooth-like sequence of binding energy. Almost every pair of electrons in the atom is more stable than the odd number. The 5th and 6th electrons are an exception.
This is where research can start or simply calculate a multipole evolution to confirm - or reject - the more stable cohesion of 5 dipoles compared to 6 dipoles around a common centre computationally.