[Python] Calculate hours in period. DST aware

I want to calculate a DST aware figure for the total hours in a period localized for Europe/London.

Given the start time, I need to generate the end time and then calculate the hours in period.

For example:
MONTHLY PERIOD

# define start
s = pd.to_datetime('2023-03-01').tz.localize('Europe/London')

>>> Timestamp('2023-03-01 00:00:00+0000', tz='Europe/London')

# generate end
e = (s + pd.offsets.MonthEnd()) + pd.Timedelta(days=1)

>>> Timestamp('2023-04-01 01:00:00+0100', tz='Europe/London')

# calculate hrs in period
(e - s) / pd.Timedelta(hours = 1)

>>> 743.0


This seems accurate and provides the correct result as, in the UK, an hour is lost in March.
However, when changing the year to 2024 and setting s = pd.to_datetime('2024-03-01').tz.localize('Europe/London'), an incorrect result of 744 is returned.

I'd like a full proof way of calculating hours in period please.

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