The start of the 2021 British Superbike Championship has been delayed until 25-27 June at Oulton Park, around a month later than originally planned.
The move has been made with a view to having spectators in attendance for the 25th anniversary year of the series.
All events will now take place beyond 21 June - the date which provisionally marks the easing of spectator restrictions at elite sporting events.
The Thruxton and Snetterton rounds have also been rescheduled.
Both those events were also to take place prior to 21 June.
The Hampshire circuit now hosts the fourth round on 30 July -1 August and the Norfolk venue moves to 3-5 September.
Meanwhile the first visit to Donington Park and the second visit to Oulton Park will both move back a week from the previous schedule, taking place on 13-15 August and 24-26 September respectively.
The official test programme will now begin at Silverstone on 28-29 April.