Add or remove excluded stay dates of one Booking.com promotion. Only the dates you send change: other excluded dates, the discount, linked rooms and rate plans, and room availability are not touched. The call is synchronous. Booking.com can take some seconds to show an accepted update: when the response has confirmed: true the promotion was read back from Booking.com with the new dates; when confirmed is false, Booking.com accepted the update but had not shown it yet, so call GET /channel_accounts/booking/promotions again a minute or so later to check. For a few tens of seconds after an update, GET may still return the old excluded dates; add and remove are idempotent, so sending the same request again is safe. Removing the last excluded date of a promotion may also return confirmed: false.

• add and remove are idempotent: adding a date that is already excluded, or removing one that is not, changes nothing. 502 means Booking.com was unavailable or the result could not be confirmed, and the update may still be applied within the next few minutes. Sending the same add and remove again is safe; before sending different dates for the promotion, wait a few minutes and read it with GET /channel_accounts/booking/promotions.
• Only active promotions can be updated (409 otherwise): Booking.com activates a promotion on every successful update, so updating an inactive one would put it back on sale.
• Dates must be YYYY-MM-DD, not in the past and within 3 years; add and remove together can contain at most 366 dates and must not share a date. Booking.com may reject dates further out than it supports, and some promotion types do not support excluded dates (400 with the Booking.com code in error_msg).
• Limited to 10 updates per minute per Booking.com property, in addition to the account rate limits; 429 responses include Retry-After.
• Returns 501 while the feature is not enabled for your account. Test on a promotion you can afford to change first.

Requires a writable access token.