A website about the Bromley North Branch Line
 
Picture
A class 466 taken from a vantage point accessible from the footpath.
Today, On my regular walk from the bus dropping off point to home, which involves a trip through Bromley North station itself I saw a class 465. The line is usually run by a class 466 EMU, which are a 2 carriage version of the class 465 (which has 4 carriages), Southeastern usually bring these out for no apparent reason or, in some cases to reduce the chances of the train breaking down in frost or snow (as there are more 'pick-ups' on a longer train)- but the first thing that stuck me was- 'bet those peak time passengers are pleased.'
And they would be, for when my Dad was living a street away he commuted from Bromley North and he told me that he regularly failed to get a seat. So, why don't they run 465s all the time?
The answer is, of course that the demand in the off-peak does not justify the use of the longer unit all day, indeed the off-peak could probably not fill a single carriage train.

There are a number of solutions that spring to mind-
1. Re-introduce the Bromley North- London direct service with a class 465, this would satisfy all overcrowding and would not be used in the off-peak.
2. Run the 465 on the shuttle in the peak and replace it with a 466 in the off peak. (seems rather obvious but I have a feeling it won't work, I'll look into it)
3. Run two 466s in a rapid service in the peak, ferrying passengers to Grove Park every 5 minutes or so as they come- they may have to wait at Grove Park but it would avoid overcrowding and the passengers would otherwise be waiting at Bromley North (or Sundridge Park) anyway (although Bromley North is much nicer to wait at in my opinion, Sundridge Park is even Nicer!) In the off peak one of the units would leave the branch and leave the other to continue the 3tph sequence. (alternitively the extra unit could wait in one of the two platforms at bromley north between the two peak times.

Website about the Bromley North Branch Line which runs between Bromley North and Grove Park with a intermediate stop at Sundridge Park