I try to always lube patches a few days before I'm going to use them but have had several occasions where I made some up for hunting season and then they sat for 2-4 months before I went to the range and actually used them. (keep your comments about my hunting success to yourself!
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I've not seen any issues with patches lubed with mink oil as of yet. My groups are the same and recovered patches look the same.
I do keep mine in an old cap tin though, they are not as exposed to the air as ones in a loading block would be.
I'm a testing kind of fella. For peace of mind, you could lube up some fresh patches for your loading block before you go out in a couple of weeks. But I'd set those old patches aside somewhere, out in the open air, and at a later date when I had a chance I'd load them up and shoot them.
You'll know for absolute certain for similar situations in the future.
I'd wager bacon wrapped backstraps that they'll shoot just fine.
Due to my afore mentioned hunting prowess, I'll need the loan of some back straps if I lose the bet.