I did same same, but in October 2018.We took on a 5 year fixed, nearly a year ago. If the economy is in dire straights in 4 years time that interest rates are at 10-15%, then i think there will be a lot more going on to worry about.
One thing I don't understand is how the government seems to have a huge pile of free cash at the moment to dish out furlough money and things like 50% off dine in food from Monday - Wednesday in a lot of places. This money will get extracted no doubt from (mainly) the high earners over the coming years

Not saying i'm in a supertax bracket or anything but it does mean as soon as I try and get extra money by working lots of overtime to make overpayments on my mortgage, I get hammered into the ground on tax payments.
It's not exactly a rewarding system for the people that work their nads off... Currently paying for Sharon and her 5 kids to eat at Pret for the first time ever which eventually comes out of my overtime work