I am on a United reservation with myself (Plat), mother (gold), dad (silver), and four other family members w/o status (general members). We are all seated in economy plus. We are headed to/from Europe connecting both ways in the US on an all-United metal itinerary.

The first flight is coming up and is J9 and 10 seats showing unreserved in first. Would love to hear any advice and recommendations on how to split the PNR (never done before). Can I call United and split before into two groups: myself and one general member passenger, and then my mother, father, and three remaining general member passengers? It sounds like if before T24, the auto upgrades would skip my big group in preference for reservations of two or less? The additional complication is that the second group has a gold and silver together - what does that do for upgrades?

The return domestic leg is currently J6 with six unassigned seats (weeks out) but it'll just end up working however we figure out the PNRs above.

Thanks!