Has it been in London since it was at the Lyric Hammersmith in 2007? That was definitely in two parts, and judging by the length, I don't suppose it was cut down particularly either.
That was the last time and the only full London/UK revival to date (Part 1 gets done occasionally). There were a few minor amendments to the Lyric/Headlong production, mainly that a chunk was cut from the final epilogue (mainly lines dealing with the politics of the time that were seen as no longer particularly relevant) There were a few other minor tweaks but that was the main change. It was also the first time Kushner had re-editied since the NT production.
Going to sound really uneducated here - is this two separate plays ie Harry Potter and the Cursed Child with a part 1 and part 2, or more like Falsettos where it is two plays which have been brought together as one.
It's a part 1 and 2 like HP. (there's a comparisson I never thought I'd make!) Kushner always intended to write a 2 parter, so while part 1 (Millennium approaches) was initally performed alone at the NT in in LA, the official 'full' version is Part 1 and 2 (Perestrokia). Part 1 can kind of be viewed in isolation and is sometimes performed on it's own, but part 2 needs part 1.
Usually it's performed like HP is now, in rep with days where you can see both parts. Usually it's taken as if it's one long play then-just with a longer interval in the middle.
Sorry probably a little more information than anyone wanted but I do quite literally have a PhD in this play