# August 2026 (/changelog/2026-08)



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## Aug 17, 2026 [#aug-17-2026]

### Citibank China Payment Rules [#citibank-china-payment-rules]

We published payment rules for [Citibank China](/guides/citi-cn-payments) via [Acme batch payments](/reference/post-batch-payments). The page covers field validation and constraints for `CN_ACH`, `CN_RTGS`, `CN_TT_INTL`, and `CN_TT_DOM`, including SAFE BOP regulatory reporting for the TT types.

#### Link to payment rules: [#link-to-payment-rules]

* [Acme Citibank China Payments](/guides/citi-cn-payments)

***

## Aug 14, 2026 [#aug-14-2026]

### Direct Debit Authorization `payerAuthorizedMaxAmount` (API) [#direct-debit-authorization-payerauthorizedmaxamount-api]

Direct Debit Authorization API responses and webhooks now include `payerAuthorizedMaxAmount`: the maximum payment amount the payer authorized with their bank, in SGD minor units.

* Only a non-zero value for Singapore eGIRO Direct Debit Authorizations, and only after the payer has approved.
* Returns `0` before approval (including on Create), when the bank did not return a payer-set limit, and for other DDA types (for example HK or Malaysia FPX). Use `precheckMaxAmount` for the Acme-side cap on those types.

#### Affected pages: [#affected-pages]

* [List Direct Debit Authorizations](/reference/get-direct-debit-authorizations)
* [Get a Direct Debit Authorization](/reference/get-direct-debit-authorizations-id)
* [Acme webhook examples](/guides/webhook-examples)

### Mock `payerIdType` and `payerIdHash` in Direct Debit Authorization test mode (API) [#mock-payeridtype-and-payeridhash-in-direct-debit-authorization-test-mode-api]

Successful Singapore eGIRO Direct Debit Authorizations in test mode now return mock payer identification fields, so you can test hash handling without a live bank.

* `payerIdType` is `NRIC`.
* `payerIdHash` is the SHA-256 hex digest of uppercased `S1234567D`.
* Live mode, Malaysia, and Hong Kong are unchanged.

#### Affected pages: [#affected-pages-1]

* [Special Test Mode Values](/guides/special-test-mode-values)

***

## Aug 7, 2026 [#aug-7-2026]

### Documentation: Maybank Singapore, Citibank Taiwan, and Banco Azteca Mexico Payment Rules Corrected [#documentation-maybank-singapore-citibank-taiwan-and-banco-azteca-mexico-payment-rules-corrected]

We corrected the payment rules pages below to match Acme's validation. The validation behavior is unchanged.

Maybank Singapore (H2H):

* `paymentDetails` and `purposeCode` must not be provided for BKTR payments. They were previously documented as optional, and the BKTR example request was corrected accordingly.
* `purposeCode` allows up to 5 characters. It was previously stated as 35.
* `receiver.bankAccountNumber` accepts digits only. It was previously stated as alphanumeric.
* FAST and PAYNOW payments must not be more than SGD 200,000 in amount. This limit was previously undocumented.
* BKTR payments are not restricted to SGD. Currency was previously documented as SGD only for all payment types.
* `receiver.bank` is validated as alphanumeric with a maximum of 11 characters, not against the BIC pattern.

Citibank Taiwan (H2H):

* The full receiver address must fit in 3 lines of 35 SWIFT characters. It was previously stated as 2 lines.

Banco Azteca Mexico (API):

* Field names in the tables were corrected to the single payment request format (for example `customerReference` instead of `payments[N].customerReference`).

#### Affected pages: [#affected-pages-2]

* [Acme Maybank Singapore Payments (H2H)](/guides/mbb-sg-payments)
* [Acme Citibank Taiwan Payments (H2H)](/guides/citi-tw-payments)
* [Acme Banco Azteca Mexico Payments (API)](/guides/baz-mx-payments)

***

## Aug 6, 2026 [#aug-6-2026]

### Maybank Singapore Payment Status Mapping [#maybank-singapore-payment-status-mapping]

We documented how Maybank Singapore (H2H) transaction statuses map to Acme payment statuses on the payment rules page.

#### Link to payment rules: [#link-to-payment-rules-1]

* [Acme Maybank Singapore Payments (H2H)](/guides/mbb-sg-payments)

***

## Aug 4, 2026 [#aug-4-2026]

### Per-payment Currency in Batch Payments (API) [#per-payment-currency-in-batch-payments-api]

The [Create a Batch Payment](/reference/post-batch-payments) API now accepts an optional `currency` field on each individual payment.

* When omitted, the payment uses the batch-level `currency`.
* When provided, it overrides the batch-level `currency` for that payment.
* The currency must be a currency supported by the payment type.

#### Affected pages: [#affected-pages-3]

* [Create a Batch Payment](/reference/post-batch-payments)
* [Batch Payments](/guides/batch-payments)