Did anything change for Anthropic cache write (cache creation) billing or metering around Aug 18?

Hi — looking for confirmation rather than reporting anything, since I may just be misreading my own dashboard.

Around 2026-08-18 13:00–14:00 UTC, for anthropic/claude-sonnet-4.6, I noticed that cache-creation ("cache write") tokens stopped showing up as a cost component on my generations, and the Cache Write Tokens series in the AI Gateway dashboard dropped sharply at the same time — while cache read, input and output all looked normal.

Could someone confirm which of these is the case?

Was there a pricing change around then, where Anthropic cache-creation tokens are no longer billed separately (or are now folded into another line item)? I couldn't find anything in the pricing docs or the changelog.
Or did the meaning of the Cache Write Tokens metric change, so I shouldn't read it as cache-creation tokens any more?

For context, I didn't change any cache_control / providerOptions configuration around that time, so I don't think my own caching behaviour changed.

I have per-generation numbers and generation IDs and I'm happy to share them privately with someone from Vercel if that would help.

Hi — looking for confirmation rather than reporting anything, since I may just be misreading my own dashboard.

Could someone confirm which of these is the case?

Was there a pricing change around then, where Anthropic cache-creation tokens are no longer billed separately (or are now folded into another line item)? I couldn't find anything in the pricing docs or the changelog.
Or did the meaning of the Cache Write Tokens metric change, so I shouldn't read it as cache-creation tokens any more?

For context, I didn't change any cache_control / providerOptions configuration around that time, so I don't think my own caching behaviour changed.

I have per-generation numbers and generation IDs and I'm happy to share them privately with someone from Vercel if that would help.