I was positive this must have been asked before, but I couldn't find it in EO forum. Here's the context: Today's Thursday. I told my friend I've sent a parcel to him last Monday. He asked whether I meant the Monday that's 3 days ago, or the Monday of last week. I was very sure that "last Monday" refers to "last week's Monday". But it seems it can also mean "the Monday just past". Is this a BE/AE issue? Or a regional thing? Or was my friend just being overly cautious and was only double-checking? Thanks in advance.