In that protocol (NEC1) the last four values (0156 0055 0015 0e48) represent a special signal sent to indicate the the button is still pressed.

The first four values (0000 006d 0022 0002) are a header, with the third value (0022) indicating the number of value pairs in the part that is sent once (22 hex is 34 decimal, indicating the first 68 values after the header are the one-time part).

The fourth value (0002) represents the part repeated while you hold the key. That corresponds to the two pairs (four values) at the end, which I explained earlier.

If I understand you correctly, you want to change it to have some fixed number of copies of the repeat_while_held part rather than have it actually repeat for the time the button is held.

To do that you must:
1) replace the 4 values at the end with N copies of those 4 values.
2) replace the 0022 in the header with the values 0022+2N (use a hex calculator, such as windows calculator in view/scientific:hex mode to compute that if you don't know hex arithmetic).
3) replace the 0002 in the header with 0000.

Changes 2 and 3 mean the entire signal is treated as a one-time part (sent the same regardless of how long or short you press the key).