These two blocks are two small tables. The inforamtion entered in A2 of each of these controls the labels in column A of the Time column in the large table.
You could simply remove both tables, and enter the start times for each row of the main table manually.
To do that:
Select both small tables.
Press delete.
Then replace the error trianges in column A with either Date and Time values, entered as time only, or with text formatted representation of the time of day.
Or you could hide both these tables by sliding them behind the large table.
To do that:
Select both tables.
Go Arrange (menu) > Send to Back.
Press and hold the shift key and tap the down arrow several times to slide the small tables behind the main table.
Regards,
Barry