I think the old oil is fine until OLM gets to 0%. I don't know why you'd arbitrarily say 5%, 10%, or 15% left. That's a half-hearted weak statement. If you trust Honda, trust them all the way, it's good to 0% (and then some, cause that's the formula with the cheapest bulk oil).
I recall the Honda Manuals says something like "schedule a service appointment" at 15%; but don't take it to mean change at 15%, they just don't want you to rush an appointment at the last minute.
Anyway, unless you change because you want a change in viscosity, like the old was 5w-20 and you wanted 0w-20 i don't think you gain anything by changing early.
But the new oil is fine too, so you don't lose anything either.
For those harping on the special breakin oil and don't dump early. Yes, probably has more moly, but it's not like he dumped after 100miles. He's got 5k miles on it and over 100hours and 10 million+ Revolutions of the engine; whatever needs to be broken in, is broken in. The oil still has life in it, if you want to keep using it; but has long already fulfilled break-in duties.