Can't say on the mags my friend..........it did take about 3-3.5 months for my wife to receive her "free" M&P9c magazine last year.
Also, took longer for the rebate a few years back on one M&P15 [$100 at the time] I bought as opposed to the other....both mailed same time...
You can call customer service for S&W and they should be able o check for you. Any time I've spoken to them they were extremely polite and helpful.
Mon-Fri 8:00AM-8:00PM Eastern Time
"OEF / OIF Vet"...still proudly serving. In memory of SGT Roger Dale Rowe...KIA Iraq, 9 JUL 2003...RIP brother.