We're going April 4-14 and I got my packet exactly 30 days prior to check in, on Saturday March 5. Same last year: we arrived on Monday April 19 and received our packet exactly 30 days prior, on Saturday March 21.
If you're checking in 10 days after me, then theoretically, you should receive your packet 10 days after me, which would be March 15, which is today. But you live farther away, which could cause a delay of an extra day, plus just the normal discrepancy in mail time, but I would think you would probably get it tommorrow, or by Friday at the latest.