Pushbutton to extend time of flow

I have several flow how finished on a preset time
How can I extended the the during a party
Normally the flow ends about 23:45 but during a party or visitors I want to extend the time by using a pushbutton on my phone

Here I use virtuele switch’s.
They can be selected as a favourite device on your phone.

Yup, also using a virtual device for this

“the flow ends” is maybe not exactly the right wording/meaning, because a flow can only be triggered/started at a particular time or event. A flow can’t be stopped at a particular time, e.g. with a flow card “At 23:45 stop the flow”.
Of course, the ending of a flow can be influenced by a timer, a build-in delay flow card or something else. But this exactly the important thing what we need to know. What does your flow end at 23:45?
So it would be helpful if you post a flow as example.

this the flow

So you actually don’t use any timer or delay function to let end the flow at 23:45.
Then in my opinion the easiest way is indeed to use a virtual switch to ensure, that the flow isn’t triggered at 23:43 at all if there is a party going on.
A flow card of the virtual switch must be added in the section And… to the flow as Is not switched/turned on.
Then you also need a second flow. Copy the flow and exchange the first flow card The time is with a flow card of the virtual switch Turned off. In addition add a flow card Time is later than 23:43.
The standard state of the virtual switch must be disabled.

How it works
If you have invited guests or are having a party, you need to turn on the virtual switch. This ensures that the flow doesn’t start at 23:43.
When all the guests have left, turn off the virtual switch. If it’s already after 23:43, the new flow is started immediately. If it’s still before 23:43, the “old” flow will start as usual at 23:43.