Someone here explained to me a couple of years ago that EO lines are actually more expensive to upgrade to FTTP as they need to do more digging - it is easier to use the shorter conduits from cabinets. Not sure if this is true.

It's not true.

They need to do more digging with direct buried cables but not all EO lines are direct buried and plenty cabinet fed lines are direct buried.

Cost is dependant on things like location (rural etc), civils involved, distance to nearest Agg Node etc.
The fact some EO lines may be very expensive to upgrade to FTTP is unrelated to them being an EO line.

The deployment of FTTP to EO lines is done identically to everyone else. The copper isn't touched and the cabinets aren't touched.

On a side note regarding direct buried cables.

If the cable is run through ducting in the garden/customer land then where is the termination point at the Openreach end? I do not recall ever seeing any Openreach tee/toby style boxes like what Virgin media use in the pavement.

If it run's back all the way to the drop point how are replacement cables run through, as surely using a cobra would end up meandering through other customers ducting (or are they all kept separate).

In reply to a post by gary333:

If the cable is run through ducting in the garden/customer land then where is the termination point at the Openreach end? I do not recall ever seeing any Openreach tee/toby style boxes like what Virgin media use in the pavement.

Our street has BT pavement chambers every 3-4 houses. I believe the DPs are in those chambers.

Interesting.

How do they provide FTTP in practice (now talking about urban areas and underground cabling)? Are there aggregation points somewhere along the route or does all cabling come from an exchange? My BT EO line is over 2 miles long. If that was ever ugraded to FTTP, would they replace it with another 2mi long fibre following the same route or would they build an aggregation point somewhere and reroute the line from my home there? Do they use existing conduits or do they need to dig up streets to get this fibre in place?

In reply to a post by gary333:

On a side note regarding direct buried cables.

If the cable is run through ducting in the garden/customer land then where is the termination point at the Openreach end?

Confused by the question.

Direct buried cables (aka DIG, Direct In Ground) do not have ducting.
They are usually armoured cables buried in the ground.

In these cases they usually leave the buried copper cable and (when possible) they install new ducting for the fibre drop wire.

There are also fibre/copper combined cables that can be installed.

OpenReach don't usually have a Toby for every property like Virgin do.
They tend to have a Distribution Point (DP) in underground chambers that serve a number of properties.

Where a property is fed by overhead cable they tend to use the same telegraph poles for the fibre. The DP is usually on a local telegraph pole.
The copper drop wire from the pole DP to the property can be replaced with a combined copper/fibre drop wire.

When FTTP is rolled out they only install fibre as far as the DP, for both overground and underground DP's.
It's only when an order for FTTP is placed by the customer that OpenReach will visit the property to decide how the final drop wire from the DP to the home should be placed.

The fibre comes from Fibre Aggregation Nodes.
These are often already out in the network.

Aggregation Nodes are also where the fibre for FTTC cabinets come from.
There's usually an Agg Node for every 3 or 4 FTTC cabinets.

In some rural areas the Agg Node can be placed at/near the exchange but for most areas the Agg Nodes are deeper in the network, nearer the homes they serve.

The route of the fibre doesn't have to follow the route of the existing copper.
The only part of the existing infrastructure that the fibre shares is any ducting/poles that may be in place.
The lack of or existence of a cabinet is irrelevant.
Where possible they use existing poles and ducting.

So it's fibre from the exchange to an Agg Node, then to a fibre splitter, then to a distribution point, then finally from the DP to your home.

If there are FTTC cabinets closer than the exchange then the fibre would likely come from the direction of 1 of them.

Some EO lines can indeed be more expensive to install FTTP than some cabinet fed lines, but this is down to their individual circumstances (location, lack of ducting, distances, civils required, etc) and not specifically because they are EO.
The same goes the other way round.

That's 'my bad' for mentioning direct buried, this was what got my brain thinking what happens when the cable isn't directly buried and where ducting has been placed to the property.

Is there simply ducting from each property to the street chamber (where the DP is). If so is this ducting shared (like VM) or are there multiple ducting exists within the street chamber?

The ducting from the final DP/chamber to the properties it serves isn't shared. Each property will have its own duct back to that final chamber.