Hello,
We have found the same issue on few boards.
MVF61NS151CMK50
MASK : 2N02G
BATCH : PTCTCTAY1626A
Vbat drain more than 1mA, instead of 10µA ( VYBRIDFSERIESEC rev 8 says IDD_VBAT max 45µA )
Seems to be a defective batch.....
Best regards,
Emmanuel