Sublets and short-term leases

Hi all, I'll be moving to the area from Canada with my partner later this spring. We'd like to start by renting a flat for a short period, like 1-2 months, to give us time to explore different neigbourhoods and find a long-term lease in a place that we really like.

I'm wondering if there are options for this besides the big platforms like Airbnb, Vrbo etc? Is subletting from a tenant who's moving before the end of their lease a thing in the UK?

Related question, are there certain months with more lease turnover than others?