what if/past

[wowenglish1]

A: What time is it?
B: It’s a quarter to 12. Why?
A: At noon, on the dot, I’m supposed to meet James.
B: On the dot? What if you don’t get there until a few minutes past four? Will you turn into a pumpkin?

I would like to know the meaning of "what if" and "a few minutes past four".

[Khosro]

A: What time is it?
B: It’s a quarter to 12. Why?
A: At noon, on the dot, I’m supposed to meet James.
B: On the dot? What if you don’t get there until a few minutes past four? Will you turn into a pumpkin?

I would like to know the meaning of "what if" and "a few minutes past four".

I would say:
What if = What would happen if

"A few minutes past four" means 4:02 or 4:03 or 4:05 or 4:09 or ... .

[Raymott]

A: What time is it?
B: It’s a quarter to 12. Why?
A: At noon, on the dot, I’m supposed to meet James.
B: On the dot? What if you don’t get there until a few minutes past four? Will you turn into a pumpkin?

I would like to know the meaning of "what if" and "a few minutes past four".

I think there's been a transcription error and it should read "a few minutes past twelve". It doesn't make sense otherwise.