Can the depiction of the English Channel  RA(T) as described in AIC Y 29/2021 be adjusted to reflect the actual airspace more accurately. Currently SD just has a very large circle containing it which extends significantly inland. I appreciate this may be caused by the coding of the AIS at source rather than a SD problem but it would be useful to have it displayed in a useful manner. Thank you.

Can you be specific about what you're referring to? On my screen I can see that SkyDemon has successfully decoded most (if not all) of the British NOTAM, showing each of the areas as precise polygons.