Cyclone IV drop in replacement confirmations

Dear Altera,

If the BANK VCCIO is 1.8V and the same package but with different LE # FPGA is drop in replace.
Where the original pin is a VCCA while different LE size same pin is a IO.
With 1.8V on VCCIO and input fixed to VCCA aka 2.5V do this introduce any issue?

As we can see the datasheet mentioned the DC input accept 3.6 or below.
-> Table 1–4. Recommended Operating Conditions for Cyclone IV GX Devices (Part 2 of 2)

So the C4 device have a protection forward diode to clamp the voltage when IO is set to input?
As long as that pin is fixed to input state do this condition function properly?

Thanks,
Brian