If you split the PNR on the outward leg, would that cause issues for the remaining GMs in E+ on either the outward or return legs, such as they loose their E+ seats assigned before the split? From reading threads appears this used to be an issue, but I'm less clear if it is still an ongoing issue today.

Also does it matter where/how you split: website, airport checkin, agent checkin, or 1K desk?