Is the oil cleaning or the debris built up in stead of being removed via the oil being changed?A good bit of carbonaceous material was broken free during this long OCI. As those carbon deposits form, they can trap wear particles in them. Then this oil, with strong cleaning ability, comes along and dissolves those deposits, kicking the trapped wear metals into suspension.
Looking at the filter, silicon, and wear metal content tells me this engine still has a good bit of cleaning to go through.