Since you show the switch-on and switch-off times of the weekly timers, you are in the LOGO! Display on.
Then you can also change the times via the display.

You need to integrate the parameters to be changed in a message text (see attachment). 

You need to integrate the parameters to be changed in a message text (see attachment).

If you now want to change a parameter, you need to select the appropriate message text.
When the message text is selected, press the ESC key for longer than 2s. Then, a black bar appears in an input / output field.
With cursor up / down you can choose between several fields.
If you select the field to change, press the OK button (at TDE > Enter).
The black bar turns now in a blinking box. With cursor up / down, you can now change the value at this position, with cursor left / right to switch the position.
When you are finished with the changes, press again the OK button and you will return to the black bar.
Now you can select with the cursor up / down to another field, or press ESC to quit the Operation.

Since the integrated web server also displays these message texts, you can also change them via the web server. Double click on the time and it will open a window in which you can then change the time.