There has been some discussion recently about the risks involved in running appliances at night unattended.
You can read a a Which webpage about it.
In the article there is no mention of the value to the wider community of avoiding the peak, irrespective of whether the delay is into the middle of the night or not.
The picture above, which is taken from the webpage, suggests an overloaded dryer, which is obviously a bad and dangerous idea.
- Don't overload appliances
- Have your appliances checked every year (it's compulsory in certain types of property)
- Don't use it as an excuse not to delay at all!
- It's more important to avoid the peak (3 to 8 pm) than to delay into the middle of the night.