Well the banks will have done a lot of research into this so a fixed rate mortgage will have factored in this risk. So over the course of the two years you will probably pay approximately the same as you would with a variable mortgage.
However, if things are tight, the peace of mind from having rates fixed could be welcome. You could also look at IIB's capped tracker mortgage. This way you have a tracker mortgage but your maximum repayment rate is limited to 4.99% APR.
Btw, I have no affiliation with IIB I just thought it was an interesting product.
As for when it will end? Who knows? If I was betting I would say the top of the cycle will be around 4.5% ECB base rate. However, nobody knows for sure and many would say it will end earlier than that. I guess it depends on inflation data.