Why the difference in times for trains from London Waterloo to Guildford?

[infobleep]

Apologies if this has come up before and I've missed it.

Today I just missed the 17:43 Guildford to Godalming service.

I was expecting the next train to be at 18:12 but to my surprise it was 18:05.

Now both trains start London Waterloo 30 minutes apart at 17:00 and 17:30 respectively.

They also both stop at Clapham Junction and Woking. So what is causing one train to take 8 minutes longer than the other?

Is it due to the Alton train ahead of it, departing Woking at 17:26 and there being s conflict if it departed sooner.

The 17:00 train was 5 minutes ahead at West Byfleet.

 

[DelW]

Apologies if this has come up before and I've missed it.

Today I just missed the 17:43 Guildford to Godalming service.

I was expecting the next train to be at 18:12 but to my surprise it was 18:05.

Now both trains start London Waterloo 30 minutes apart at 17:00 and 17:30 respectively.

They also both stop at Clapham Junction and Woking. So what is causing one train to take 8 minutes longer than the other?

Is it due to the Alton train ahead of it, departing Woking at 17:26 and there being s conflict if it departed sooner.

The 17:00 train was 5 minutes ahead at West Byfleet.

I saw something similar in the timetable a few weeks ago, and then it did seem to be due to one of the services each hour having an extended dwell time at Woking, apparently as a result of a conflict at Woking Junction.