what time of day does the lunar new year start?

Unlike the universal New Year observed on January 1st, Chinese New Year is never on a fixed date. The dates vary according to Chinese lunar calendar, but generally fall on a day between January 21st and February 20th in the Gregorian calendar. Thus the Chinese new year begins from Jan.1st on Chinese lunar calendar.

Here under are Chinese New Year in the following years for your reference:
2020 Jan. 25 Saturday Jan. 24 - 30
2021 Feb. 12 Friday Feb. 11 - 17
2022 Feb. 1 Tuesday Jan. 31 - Feb. 6
2023 Jan. 22 Sunday Jan. 21 - 27

Unfortunately, Amy's reply is completely unhelpful and does not refer to my question in any way. The information she gave is already known but the simple question I asked is WHAT TIME OF DAY is the new day, and particularly the New Year, deemed to start - e.g. 0001 hrs Beijing time, or 0001 hours local time wherever you are.

For example the universal New Year is deemed to start at midnight local time world-wide so is different in each time zone. The UK has just left the EC specifically at 2300 GMT because that is midnight in Brussells. A child is born at 2355 on a specific day and it's twin born on 0005 will be deemed to have its birthday the next day.

So did the current Year of the Rat start at midnight, sunset the previous day (I believe this to be the Jewish custom) or some other specific time, and is this a universal time moment for the whole world, or based on local time where you are?

I would be grateful for a simple answer to the simple question, WHAT TIME OF DAY is the Chinese New Year deemed to start?

Many thanks,
William Lyons

As I know, the time of New Year is deemed to start 0001 hours Beijing time.