Please help on formula to add pauses to order time

[Kamolga]

Hi,

I have an issue with adding pauses to a production machine schedule.
I would need to say when will order 1 and order 2 finish.
Here is an example for Monday:

	A	B	C	D	E
1		Machine	Start	06:00
2	Shift A	Pauze 1A	Start	09:00
3			Stop	09:15	00:15
4		Lunch A	Start	12:00
5			Stop	12:30	00:30
6		Pauze 2A	Start	14:45
7			Stop	15:00	00:15
8	Shift B	Pauze 1B	Start	17:00
9			Stop	17:15	00:15
10		Lunch B	Start	19:00
11			STOP	19:30	00:30
12		Pauze 2B	Start	20:45
13			Stop	21:00	00:15
14		Machine	Stop	23:00
15
16	Orders	Time to produce	Start	Stop
17	Order 1	08:00	=D1	=C17+B17+????
18	Order 2	09:00	=D17	=C18+B18+????

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Thank you in advance for your help!

 

[mole999]

something like TIME(0,0,30) for 30 seconds, would need playing with

 

[Kamolga]

Yeeah that part is easy (adding hours to hours, minutes to minutes), the part I fail is the if-and-or:
Adding the 15 minutes if it end after first pause is easy, but let's say it was supposed to finish 10 minutes before lunch, due to pause, it should finish 5 minutes after lunch.

This simple matter blocks me