BritRail Pass Question

Us in the UK are generally not well informed on BritRail passes as we can’t buy them here.
But one thing to consider is that it can often be cheaper to buy Advance* tickets if you have a fairly fixed itinerary. The BritRail pass is good when you want the ability to just turn up and jump on a train rather than have a fixed plan, but be aware that the pass will not automatically give you a reserved seat, which can be useful on longer trips. You can make reservations but that is an extra task and takes away spontaneity.
You also might be able to make significant savings if you are eligible for a railcard. If you are under 30 or over 60 or are a couple travelling together you can buy a railcard for £30 and get 34% off all ticket prices.
* Advance fares are a type of ticket that you can buy cheaply ahead of time, but they commit you to a specific train. Miss it and you will need to buy a new ticket.
You really need to do some sums yourself or give you an idea of your plans for us to give you some idea.

Thanks. I don’t qualify for a rail card. I’ve done the sums as best I can checking average ticket prices between my destinations, and it seems like a BritRail pass would probably be a good idea because it would be cheaper. Also, I like the idea of the “hop on, hop off” flexibility it would provide. I’m going to do a lot of sightseeing and hiking, and while I can figure out what days I’ll probably need the tickets, the time of day I’ll need them will depend on when I get done hiking, sightseeing, etc. on those days, and I would prefer to have the peace of mind that if I plan to get to the train station at 17:00 but I want to linger at a place unexpectedly, I can just get to the station an hour later and catch the next train.

You can purchase Rover Tickets in the UK for different regions. Please see:> https://www.nationalrail.co.uk/ticket-types/promotions/?promotionType=ranger-rover

There is also an All Line Rail Rover (7 or 14 day), but that is seriously expensive- around twice or more the cost of a Britrail pass for the same duration.
It used to be a bargain, but few people these days could make the All Line Rail Rover pay for itself, with all the advance fares that now exist.
Compared to the UK versions of a regional or national Rover ticket, the Britrail tickets for a similar region are always far better value- a rare case where international visitors pay less than the residents of the Country.

To answer your question there seems to be nothing in the rules to stop you from having multiple Britrail passes in a year.
I don't see why you could not have 3 x monthly passes if you wanted to.

I didn't answer your question about the London Pass. As far as I know there is no 8 day pass - you can have any days up to 7 and then 10.
The London Pass is primarily designed to provide discounts on a number of attractions in the city For most visitors it is not a good deal as many major attractions such as museums and galleries are free to enter and there are many 2 for 1 deals available for paid attractions. But, if, as it sounds like, you will be by yourself it could work for you.
But what it is not worth is for use for transport around London. The Pass will give you a Visitor Oyster card with some credit. Contrary to the implication on their website this will not be enough for free travel for the period of the pass. You can get the same deals just by using a contactless card or Phone or Smart Watch Pay. As well as this the prices quoted on the website for travel are out of date.

The London Pass referred to by John New is a totally different product from what you are proposing to purchase.

That London Pass is for visiting central London Tourist attractions, and is of debateable value, as stated.

You are proposing to buy the 8 days in a month Brit Rail London Plus Pass- for the benefit of others that does exist as you state. It is very good value and covers train travel in the whole of what used to be called the Network South East area and in fact beyond as far as Stratford on Avon (via Banbury), Bath, Bristol and Worcester. I am sure that you understand it is not valid on tube, bus and tram services within London.
It does cover the Elizabeth Line in from Heathrow- as that is a National Rail service, not a tube service.
If you have done the maths and it works for you, great.
There is no equivalent rail rover ticket for UK citizens.

We often tell visitors to the UK to make sure that they quote the full name when they are here, as there are many similar names. there is the possible urban myth of travellers arriving at Paddington and asking for Oxford, being sent on a train to the city when they wanted Oxford St.
In this case it seems there are two products quite different that have virtually the same name.

The correct name for the London one is the Britrail London Plus Pass. They used to market it as a Britrail London Pass but stopped that some years ago due to the confusion presumably

I have never seen anything to suggest you can't buy more than one Britrail pass in a year.

Ok thank you very much