In relation to AWE's articles on sat - sitting and stood - standing: Charles Moore quoted Oliver Kamm, "Word expert on the Times", in The Spectator’s Notes in The Spectator, 17th February 2018 (p. 11), on line at https://www.spectator.co.uk/2018/02/oxfam-is-the-harvey-weinstein-of-aid/ as saying
“The replies you’ve received are in error if they tell you that ‘strict grammar’ requires I am sitting. The correct answer is that I am sat is ungrammatical in formal English but grammatical in many other dialects of British English and increasingly used in informal registers. There is nothing wrong in any of this; different varieties of the language have different rules, but all dialects exhibit a complex system of grammar and are able to convey a full range of meanings. My concern, as language pundit, is to ensure that all children (and adults) are able to use Standard English fluently but this aim doesn’t (and shouldn’t) require that non-Standard dialects be stigmatised as improper and ungrammatical.”
Kamm's stance on 'grammar' seems eminently sane to AWE, which agrees wholeheartedly.