Collected good-byes! (Brexit extra edition)

Sut mae, gyfeillion!
It’s Brexit Day. Mae diwrnod y Brecsit wedi cyrraedd – anhygoel!!! I can’t believe the day has come to say good-bye. Let’s do this in style and yn Gymraeg, of course.
So how do you say good-bye in Welsh? There certainly is ample choice:
Hwyl!
Hwyl am y tro!
Hwyl fawr!
Pob hwyl!
Ta-ta!
Ta-ra!
Ta-ra rwan! (North Wales)
Wela’i chi! – See you! (plural and /or formal)
Wela’i ti! – See you! (informal + singular)
Wela’ i chi eto! – See you again!
Da bo! (South Wales)
Da bo chi! (South Wales)
Cymer ofal! – Take care! (informal + singular)
Cymerwch ofal! – Take care! (formal and / or plural)
Take your pick! And if you have anything to add to this list, please do let me know in the comments. Local or personal variations welcome, too – diolch!
Hwyl fawr, Brydain! We’re sad to see you go. Let’s hope things will turn out for the best, eventually. In the meantime: Cymerwch ofal!
Wela’ i chi nes ymlaen!
Cofion,
Siw