Due to transceiver design, the Intel® Stratix® 10 L/H-tile, the Intel® Stratix® 10 E-tile, and the Intel® Arria® 10 transceivers are not preserved when the device remains powered and unprogrammed for an extended period of time.
In order to avoid the problem, users should do one of the following.
A). Program the FPGA as soon as practically possible and also ensure that unused channels to be used later are protected using the QSF assignment PRESERVE_UNUSED_XCVR_CHANNEL.
Please refer to the latest user guide for details on how to apply the PRESERVE_UNUSED_VCXR_CHANNEL QSF in the Intel® Quartus® Prime software.
or
B). Leave the FPGA unprogrammed for a cumulative period of time which is less than 1 year at a junction temperature less than 60C
or
C). Please contact your local Sales representative, or submit a question or request at the My Intel support page.