Oyster Caps - Zone 1-2 Cappted travel with Single Ticket ontop

Question

Can someone please explain this?

I did one journey from Zone 8, and the rest of my time was spent in Zones 1-2. I have a 16-25 Railcard on my Oyster so the Zone 1-2 cap is £4.35 and the zones 1-8 is £8.

So my question is - assuming that Oyster works out the cheapest journey at all points why wasn't I capped? Yes - I didn't meet the zone 1-8 cap, but I definitely did for the zones 1-2 cap with my travel round there. Therefore shouldn't Oyster cap my Zones 1-2 travel separately and then have the zone 8 single fare on top. It seems in my case I have not been charged the cheapest fare.

See pic:

Tried contacting customer services, they said they 'thought' zones 1-2 would cap if I traveled around there first and then made my zone 8 single travel, but not the other way round which I did.

Answer 1

Oyster capping is a complicated beast, but I think I have an answer for you.

There are two caps - Anytime and Off Peak

Anytime for your card is set at £6.60 for Zones 1-2

Off Peak for your card is set at £4.35 for Zones 1-2

Journeys are tallied against the running totals of all applicable caps, so all journeys are tallied against the Anytime cap but only some are tallied against the Off Peak cap.

Your Zone 1-2 travel is split across both of those caps, with all three journeys being tallied against the Anytime cap running total but only two journeys being tallied against the Off Peak cap running total.

Your cap totals are thusly £4.80 for Anytime and £3.20 for Off Peak in Zones 1-2, so neither cap was reached.