Reading the comments - it's a great debate, I thought I'd add in my $0.02 worth.
Firstly is the possible conversion or sharing with the trams. A lot of noise has been made with the "Trams to Lytham" group and they have carried out their own study - all be it somewhat biased in favour of light rail - into bringing trams into Lytham. Building costs, target market, usage, competition from bus operators and ongoing costs of ownership are just prohibitive factors in having a light rail system from Lytham to Blackpool. Extending it the 6 miles from Lytham to Kirkham would be throwing money down the drain as beyond the east end of Lytham, there isn't anyone living there that would require a light rail system (otherwise Wrea Green station would have re-opened before now). The thought of having to change at Kirkham to get to Preston would put a lot of people off and having to purchase a tram ticket followed by a train ticket would probably increase the fare substantually (that's me speculating however).
Going the other way, changing from the SF line to trams requires a short walk from either Squires Gate or Pleasure Beach to the tramway. If there was money to burn then build a spur from the existing tram line to Pleasure Beach along Burlington Road which would give an easy way to get to Blackpool. You would be quicker to take the bus however.
There's plans (or there were) to completely revamp the Central site -
https://www.blackpool.gov.uk/Your-C...pool/Blackpool-Central/Blackpool-Central.aspx - Covid might have scuppered those plans though. Can't see the council wanting to give up revenue generation car park spaces, so any extension beyond that wouldn't happen.
Times wise, taking the timings of RTT, 2 TPH could be accommodated:-
Kirkham 0
Moss Side 6
Lytham 10
Ansdell 13
St Annes 17
Squires Gate 20
Pleasure Beach 23
Blackpool South 25
Kirkham 30
Moss Side 36
Lytham 40
Ansdell 43
St Annes 47
Squires Gate 50
Pleasure Beach 53
Blackpool South 55
Blackpool South 0
Pleasure Beach 2
Squires Gate 4
St Annes 8
Ansdell 11
Lytham 14
Moss Side 19
Kirkham 25
Blackpool South 30
Pleasure Beach 32
Squires Gate 34
St Annes 38
Ansdell 41
Lytham 44
Moss Side 49
Kirkham 55
Which would put the passing loop in between Lytham and Ansdell. Would you need an additional platform at Ansdell or the 3 miles of double track as mentioned in the report? Possibly overkill and would make the project unaffordable.
Rolling stock I don't think is an issue. Taking the existing services (Blackpool South to Colne / Ormskirk) then you have only 8 miles under the wires between Kirkham and Preston. If you ran services to say Manchester or Liverpool, then using the class 769 once available would be a possibilty, but that's getting very speculatitive.
Will anything happen though? Sadly I think this thread will still be going in 2030.