Input data in data tables

I have to design a data table which is going to be 288 rows and 15 in size. I want to make it easy for users to input data efficiently. The data covers an entire day, in 5 minutes intervals, i.e. (60min * 24hr ) / 5min intervals equals 288 rows.

As per research this is how they input data:

  1. Most of the users put same data across columns
  2. During some critical situations they put similar data upto some rows e.g. till 60 rows data will be same, next 40 rows data will be same and so on.
  3. Users sometimes do copy-paste data directly from excel sheets.

I was planning to have a collapsible table where users can select time duration and enter bulk values which will populate for that entire time duration. But If I do this, copy and paste from excel will be an issue.

Updated: The table attached is the old design with 48 rows, now it has to be updated to 288 rows. And users will try to put repetitive data across number of some set of rows(depends upon the situation, can't predict it).

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