Are you looking for a job in the northern or southern hemisphere?
Usuall starting, changing, hiering cycle is quarterly starting 1 January.
Depending which cultural cycle you belong to one has usually 4 weeks to 3 month notice period.
Clients usually wake up late and contract last second resulting in majority of design contracts starting in spring.
Ideal situation for an office is to aquier new jobs and time delayed new staff acycli to the workload.