Im’ Moroccan, but i don’t remember seeing any other country celebrating on 27th.
In the east they know well that it can’t be surely the night of 27 (which is after the sunset of the 26th day), because in the hadiths, it’s said that the signs of it is the rain, & cloudy sky the next morning, because the Prophet peace be upon his soul dreamed making soojood & his forehead was wet & dusty.
In other Hadiths (& they’re all Sahih) it says that the night differs every year, so it can be the 21st this year, & the 25th next year. this is based on that the prophet & companion witnessed the signs in different days every Ramadan.
i remember last year, that the 27th night was a rainy night, this year & after a hot summer, the 21st night was the first rainy night & we’re still in summer. i live in Casablanca but i saw in the news that it was rainy all around Morocco, i also saw other countries having flood after this first raining night.
The following night (23th) was rainy too. & today is 27th, we still have the 29th.
It was revelated to the prophet, but when he came out to tell people, he found some problems going on & got busy trying to solve them & Allah made him forget it. so that the muslims won’t know which night it is exactley, hence they get busy in worship in all those nights & avoid getting in trouble in the holiest days of the holiest month.
those rainy signs were all what the prophet could recover. peace be upon his soul. & thank god for everything.