I hope not, Rachel. You might be breaking both the regs and the guidance.........unless you left it moored at the "border" mid channel for Chris to swim out to retrieve from the Thorney shore!!!
....but couldn't it be fun - engineering a legal route to achieving it!
By the way, the original link is now :-
https://www.britishrowing.org/2020/12/rowing-and-tier-4-local-covid-alert-level/and this is further clarified (!???!) by the newly re-oriented ARA covid advice version 8.2 (which is still current, except for the definitions of Teir 4). See especially pages 10 to 15, of which 11 to 13 are the most relevant. Also there are bits for us on pages 21, 29 to 35, etc.
https://www.britishrowing.org/wp-content/uploads/2020/12/201202-Managing-COVID-19-v8-2-1.pdfFor once, Sport England doesn't have reams to say about unfortunates in Teir 4 like us, but you can find the latest here:-
https://www.sportengland.org/news/what-new-tier-4-means-sport-and-physical-activity-england>>