I invented a new oxymoron this morning:
“Prepared In Advance”
two others coined by me, to which I owe my immeasurable fame, are:
“A Dry Wetsuit”
and
“A Wet Drysuit”
A couple of my favorite oxymorons (besides the ones I invented) are:
“Random Order”
and
“Jumbo Shrimp”

Perhaps “Prepared in Advance” is not an oxymoron, but a redundant phrase…….