Oyster travelcard query

[WideFootWelly]

I know the website says I must always touch in and out so they know where the journey began and can charge me the correct fare...

But what if you are on a train that originates outside of London and have a ticket that covers you to the travelcard zone, and then an oyster travelcard which covers all zones?

I'm getting conflicting answers, and I don't want to end up with a penalty fare!

TfL helpline said it would show as an incomplete journey, but there would be no charge as the oyster covers all zones.

Greater anglia chat helpline says get off the train, touch in/out on oyster and get back on the next train (do not want to spend my life doing this!), I asked what if the train doesn't stop at the boundary station and they said take one that does.

But their website gives conflicting information, it says:

The train does not need to stop at the boundary station for the combination of tickets to be valid

https://www.greateranglia.co.uk/tickets-fares/daily-tickets/oyster-cards

Does anyone have any experience of this?

If you have an oyster travelcard, but travel in from outside London using a paper ticket for that part of the journey, do you get off the train to touch in/out and back on the train again? Or do you just touch out with your oyster when you get to London?

Many thanks for anyone that can help...the different answers are driving me mad!

Paper ticket is no bother, just put it through the machine.
When you get off at the end of your paper ticket journey then you touch in with oyster card/ bank card. And do the same when you are going home. Touch out then use paper ticket for the rest of the journey

Sorry, I didn't explain well...

The train runs from Southend to Liverpool street, and my travelcard would cover the Shenfield to Liverpool street part of the journey. My paper ticket would cover the Southend of Shenfield part.

I recently had a similar issue with my London Freedom Pass. I was travelling from an overhead London station to Woking via Clapham Junction return.
When I was changing trains at CJn I asked the ticket seller/ inspector that was on my platform about this issue as my pass was only valid till Surbiton. He sold me a Surbiton to Woking return. On my return trip the guy who was checking tickets on the train asked to see both my return ticket and my pass. He informed me that recently they have introduced a penalty if you don't have a ticket while on the train. So you cannot just go to your destination and pay the appropriate fare.
I explained that my station is unmanned and therefore I would not be able to buy my ticket before leaving my local station. He said that the new ticket machines now have a facility to buy your ticket from the station at which point your Freedom Pass ends.
I don't think this deals with your scenario but I would just make sure you have a valid ticket for the complete journey before you depart to avoid paying a penalty.
I hope the above is of some help.