This is what it says and you'll find this info in the FAQ....
"Checks are mailed only once a month on or before the 10th of the month to the postal address on your profile, so please make sure you request your cashout at the beginning of the month and that the information on your profile is accurate. Checks are valid for a period of 60 days from the date of issuance. It is the responsibility of the recipient to cash or deposit checks in a timely manner consistent with the 60-day time frame. Any check not cashed within the validity time frame is subject to cancellation."
Notice that it says 'mailed'. Ok, what day is the 10th this month? It's Sunday. Mail does not
run on Sunday in the USA.
I've never really thought about it because I always assume I will get it when I get it and I have
always got it.
My guess is, they'll actually do the checks before Sunday.