Online Table pricing for infrequent use

[Malthe]

According to the pricing page, the minimum cost in using this product is 1 DBU per hour.

Often times, access to such tables comes in bursts with many periods of idle time. How is infrequent use factored into the pricing? This is also important for setups where you have environments that are less active, e.g. testing, qa, etc.

[Walter_C]

Online Tables are billed only during periods of active usage (plus the 15-minute scale-down window), making them suitable for both bursty production and infrequently used test environments, as long as you are aware of the minimum charge periods and storage/sync components

[Malthe]

As far as I can tell, the minimum charge for an online table is DBU-cost x 24 x 30 per month, i.e. around $720 per month.

Is the 15-minute scale-down window documented somewhere?

With a 15-minute scale-down window, assuming just one access per hour, that should then result in a cost of DBU-cost x 1/4 x 24 x 30 per month, i.e. around $180 per month–is that correct?