Time Between Arrival and Flat Check-In

Do a search on "left luggage victoria station" - or whatever you mean by Victoria - you should get a numer of hits from Stasher, Bounce, etc. Store yor bags and find a nice spot for breakfast.

First, I don't think you have as much time to kill as you think you do. You may arrival at 7.15 but it will take at least an hour, get off the plane, use the restrooms, deal with immigration/passport control and customs. Second, why take the H Express? It doesn't go to Victoria Station it is fast and expensive. Use the slower, cheaper tube to V station. Once at Victoria 9;15. .30, Use the luggage storage and take a walk by Buckingham Palace -- just a few blocks away. That should kill most the time needed prior to 11.

If you land at 7.15, you can expect to have disembarked, got through passport control and have your luggage by 8.00am approx. If there's ever a delay at Heathrow, I find it tenda ro be luggage. Give yourself 15 minutes to walk to the station for the Heathrow Express, perhaps wait for it to arrive (say 5 mins) and 20 minutes to Paddington. So you should arrive about 8.45, all being well. And if you've bought tickets for the HEX, make sure you get on that train and not the Elizabeth Line train as they both use the same platform, but HEX tickets are not valid on the Elizabeth Line.

Luggage storage is one option, alternatively hang on to your luggage and have breakfast at Paddington (or Victoria). Plenty of cafes etc in both stations. There's also a McDonald's opposite Paddington that seems to always be full of people with luggage.

Are you planning to take the tube from Paddington to Victoria?

And picking up on Frank's comment, the tube will actually take about the same time at HEX to Paddington + tube to Victoria. But it will be a lot cheaper.

You don't need to use a stasher or whatever.

All main line stations in London have on site left luggage offices.

At Victoria it is near Platform 9, just behind the Wetherspoons pub. That would be a good place to have breakfast or there is a food court upstairs in the adjacent shopping centre.

Once your luggage is left there, and you are fed and watered, to keep awake you could walk down to Westminster Abbey and Parliament- about 15 minutes or so. There is a bus back every few minutes.

Or, having reached Westminster, then left up Whitehall past Downing Street to.Trafalgar Square, then down the Mall to Buckingham Palace, then back to Victoria Station. I know all that well, but could easily kill an hour doing that walk.I

Or at Paddington go round to the Little Venice Canal Basin. From there You can walk.along the towing path in either direction as far as you could ever want. That would be a nice place for breakfast

You are arriving in the commuter peak, or just on its shoulder as you are I am more than happy for you to take the Heathrow Express for the greater comfort and space (especially with kids) over both the tube and the Elizabeth Line, which will both get very crowded on their way in at that time of day.

if you haven't purchased your ticket on the HE yet, don't. I agree with the others that the Underground (Tube) is a less expensive way and will be about the same time getting from Heathrow to Victoria Station. (And less walking.)

PIccadilly line from Heathrow to either Hammersmith or Barons Court, get off, cross the platform (about 20 feet) and get the District Line to Victoria Station.

Yesterday, neither the Heathrow Express nor the Elizabeth line was running much of the day due to emergency repairs. It caused quite a scene at their station at T2/T3. (I was there.)

If I were you, I would stick to your original plan. Take the Heathrow Express, store your bags at the Paddington Station Luggage Storage and then go out and enjoy London. Get your luggage at 2pm and head to your flat and power through your day until you are exhausted.

The reason people say store your bags at Victoria over Paddington is because there are many sites within walking distance of Victoria and not so with Paddington. (If you are looking for shops and restaurants, Paddington is fine.)

If you leave the bags at Victoria, you don't need to travel back to Paddington to get them and then to the Victoria area to your flat.

Thanks everyone. We do have tickets on the HEX because I got them AGES ago steeply discounted and my kids are free. So price wise, it actually worked out better. I think we’ll make our way to Victoria, store luggage (I was trying to book ahead with Stasher, bounce, etc. because it seems cheaper per bag than left luggage at the station, but it might be worth the convenience to pay more). I had originally planned on walking down to Buckingham Palace, through St. James Park, over to Westminster, etc., so sounds like we’ll just stick to the original plan with a few tweaks here and there for timing. We’ll stay in that general area so we can get back to the flat relatively quickly for check-in regardless of when we actually reach the city and regardless of where our wanders/meals take us. Thank so much!

You can book a day room at lots of hotels in London. Some friends of mine were in this position travelling with teens last year and booked a hotel room for the day until they could get into their Airbnb. It worked perfectly to rest and recover. They were short haul but their flight got moved to 6am which meant no sleep the night before.

"the rental agency said “just sit at Heathrow until 10."

You've got great advice from the other posts and I just wanted to say this is the dumbest piece of advice I think I've seen in a long time!

And, I'm not sure if this will work for you all as a family or not BUT I had great luck with using the jet lag app called Timeshifter last summer. I had terrible jet lag a year ago April and needed to do something different for a trip last August. I had seen the Timeshifter app discussed on the forum and decided to give it a try as it's free for the first trip. I was surprised it worked so well that I had no jet lag going or coming back home. I was just doing it for myself so I could juggle my schedule and make myself be compliant. I also fly from the Inland Northwest so may have longer airport/flight times than you do especially if you are from the East Coast.