consolidate date time in cells

[FROGGER24]

I am working on a spreadsheet and need to consolidate the date and time in column B, once the date and time have been merged into one cell the delete rows where the cell in A is blank. this will need to be able to run on various lengths of rows. thank you

camin cargo.xlsx
	A	B
3	Expected Results	Date/Time
4		3/26/2021
5	3/26/21 1:30	1:30:10
6	3/26/21 1:29	1:29:50
7
8	3/26/21 1:28	1:28:13
9		3/25/2021
10	3/25/21 4:11	4:11:07
11	3/25/21 4:04	4:04:00
12	3/25/21 4:03	4:03:04
13	3/25/21 5:15	5:15:12
14		3/24/20
15	3/24/20 9:25	9:25:38
16	3/24/20 8:59	8:59:22
17	3/24/20 8:58	8:58:34
18	3/24/20 8:27	8:27:43
page 2

Cell Formulas
Range	Formula
A8,A5:A6	A5	=$B$4+B5
A10:A13	A10	=$B$9+B10
A15:A18	A15	=$B$14+B15

 

[FROGGER24]

I found a solution, with the use of helper columns

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Range("AD4:AD" & Cells(Rows.Count, 1).End(xlUp).Row).FormulaR1C1 = "=IF(RC[-28]="""",RC[-29],"""")"
Range("AD4:AD" & Cells(Rows.Count, 1).End(xlUp).Row).Value = Range("AD4:AD" & Cells(Rows.Count, 1).End(xlUp).Row).Value


Range("AD4:AD" & Cells(Rows.Count, 1).End(xlUp).Row).Select
Selection.SpecialCells(xlCellTypeBlanks).Select
Selection.FormulaR1C1 = "=R[-1]C"
Selection.NumberFormat = "m/d/yy h:mm;@"

Range("AE5:AE" & Cells(Rows.Count, 1).End(xlUp).Row).Value = Range("A5:A" & Cells(Rows.Count, 1).End(xlUp).Row).Value
Range("AE5:AE" & Cells(Rows.Count, 30).End(xlUp).Row).Replace What:="AM", Replacement:=""
Range("AE5:AE" & Cells(Rows.Count, 30).End(xlUp).Row).Replace What:="PM", Replacement:=""

Range("AF5:AF" & Cells(Rows.Count, 1).End(xlUp).Row).FormulaR1C1 = "=RC[-2]+RC[-1]"
Range("AF5:AF" & Cells(Rows.Count, 1).End(xlUp).Row).Value = Range("AF5:AF" & Cells(Rows.Count, 1).End(xlUp).Row).Value>

Any ways to make more efficient?