How long for a hot water tank to heat up?

[2020notQuiteAsPlanned]

We have a large hot water tank - 2m high so I think 300L
If the radiators are off, how long would it take for the boiler to heat it?
Trying to cut back on our dvv BBC edgy use but don't want to run out of water for baths and showers for everyone!

Argh. Sorry. Trying to cut back on our energy use!
Nothing edgy!!

I hour does us - on a timer in the mornings

5 people

That said we need to put in on on the evenings occasionally if a couple of people want baths not showers.

Wow - one hour a day?
Need to cut ours right back then.
It's on for 2 hours morning and evening!

Ours is on for 1.5 hours a day. 2 adults and a small child and we never run out of hot water.

Tank should be enough for showers but you will still need some hot water for washing up , hand washing etc through the day and if there is a chance some people will want evening showers then heat water twice ; morning and evening.

Have cut it back to 1 hour in the morning and same again in the evening so will try that and then see if I can cut if further.
The towel rails in the bathrooms run on the same system so that way towels will still dry and bathrooms will warm up.
Baths are a rare event here but will remind everyone to bump the HW for an hour if having one!
Thanks all!