If their calculations are showing Dec 2001, then why do you care about a month or two? It's hitting the SOL soon either way. If you pulled your credit report directly from the CRAs, they will show what they think the current drop off date is (see AnnualCreditReport.com for your free yearly one). And don't bother disputing over a difference of a couple of days in the same month as it may not really matter.
This is just my opinion and I'm not an expert but the due date on the statement that you last paid on, is your last payment (well if you paid late, then they may try to use the next statement's due date).
I'm having a hard time following what you posted, but here it goes. It looks like you paid your statement that was due on or just before Oct.17 late and it was credited as being paid during your due date of Nov. 17th statement. So you were late and the amount you paid is probably less then what was minimumly owed on Nov.17th, but since they received a payment during that billing cycle, they seem to be taking the Nov.17th due date as the date last paid (I'm not saying it is right). So they are saying that the first statement that you MADE NO PAYMENTS WHATS SO EVER on, was the statement due in December. So they are using Dec.17th as the date of 1st default (assuming this was the due date). Now, technically, you didn't satisfy what was due on Nov.17th and were short on the amount you paid (since it was the amount owed from the previous month), but you did pay something and thus they can use this date if they choose.
Personally, I would not bother disputing over a month difference unless you need a loan ASAP and a month will make a difference. Most creditors I have, when things fall off, they don't use the actual day of the month. They just use the month itself, so at the beginning of the month is when things fall off. I'm not saying this is the cas with Cap1 as I don't know. They may wait until the 17th.
