Max10 - high speed IO, low speed IO and something between

Hi All,

I am going to use 10M50SCE144 chip in my design and I am wondering about the difference between different types of IOs. According to the datasheet, there are two types of IOs - high speed IOs and low speed IOs. The datasheet has different tables describing the difference between those two types in different differential standards, but I am going to use the IOs as single ended 3.3V IOs and I need to achieve 133MHz speed on few of those pins. The question is, is it possible to use low speed IOs with 133MHz clock or I must use high speed IOs?

Another question, the pin out table has few pins that are neither high nor low speed - the IO performance column is just empty for for pins (for example, pin 50 and pin 62). What is so special about those pins?

Thanks,

Alexey.