"The subjunctive mood is in its death throes, and the best thing to do
is put it out of its misery as soon as possible."
Maugham, WS (1949) A Writer’s Notebook
There is no clear answer to the question of whether modern British English has a subjunctive form or not. I have always felt that there is little point in talking of a past subjunctive when only one verb, BE, has a recognisably different form for the so-called 'past subjunctive', first and third person singular were. Huddleston & Pullum, in The Cambridge Grammar of Modern English(2002.86-88), consider there is no justification for a speaking of a past-subjunctive mood; They write "It is much more plausible to say that irrealis were is an unstable remnant of an earlier system - a system that has otherwise been replaced by one in which the preterite [= indicative - tunny] has expanded its use in such a way that it now serves to express modal politeness as well as past time". Quirk et al, in A Comprehensive Grammar of the English Language" (1985.155) do consider this to be a subjunctive form, but concede that it exists in practice only as a 'WERE Subjunctive'. Many speakers today to not use this form at all, except in the fossilised expression 'If I were you'; even here, was is commonly heard.
(Incidentally, for those who consider the use of was 'uneducated', I have a list of its use and/or defence by lexicographers, teachers, professors (of Logic, English Language and Literature, Linguistics) including:.
Sir Alfred Ayer, R W Burchfield, Sylvia Chalker, Sidney Greenbaum, Rodney Huddleston, Geoffrey Leech, Somerset Maugham, Tom McArthur, Geoffrey Pullum, Lord Randolph Quirk, Jan Svartik, Michael Swan, G H Vallins, Edmund Weiner, George Yule, etc.)
The present subjunctive (recognisable only in absence of the -s suffix in the third person of all verbs except BE, whose subjunctive form is be in all persons) is used by some people, especially in more formal writing. However, for the majority of native speakers, it survives only in such semi-fossilised expressions as *Long live the Queen".