ONE'S NUMBER COMES UP

Dear native speaking experts,

Could you comment on the expression ONE'S NUMBER COMES UP as in:

My number finally came up, though. I just accepted a job in New York.

I've been fairly active in the development of backcountry skiing around the area and unfortunately, my number finally came up," he said.

How does this phrase correlate with the expression ONE'S NUMBER IS UP:

I think that the manager's number is up and he will soon be fired from his job.

Thank you,
Yuri

My number came up. See www.phrases.org.uk bulletin_board 12 messages 981.html