I have seen this issue. The SEPM console reports the client have AV's and PTP's older than 7 days but when you remote into the client it shows the correct current date for them. From the client, you can issue an Update Policy and see that it checkes in with the SEPM because the last check-in date in the SEPM changes but the AV and PTP dates do not update. Most of the time I can run LiveUpdate on the client and let it finish. I then Update Content and then check the SEPM. After the last check-in date updates, most of the time the AV and PTP's update in the SEPM as well.
I don't know why running LiveupDate causes the SEPM to start updating, but it does at least one time.
Sincerely
Bruce Singer