Funny thing is, 3 year contracts are not standard
Most of the other companies have their MIS solutions listed on the GCloud 12 procurement framework site. Which awards 2 year contracts, with options for 2 1 year extensions at the wish of the customer.
At least 1 of their competitors is explicitly advertising 1 year contracts as well.
So, where they got the idea that 3 year contracts are standard from is a mystery.