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New Burst Protection Algorithm

To protect users against surprise charges, FeedMail covers the cost of sudden bursts of updates. The initial algorithm, only charging once a day, was too simple. Many feeds regularly see multiple updates a day and the burst-protection algorithm was artificially subsidizing these feeds.

FeedMail is now using an updated algorithm to protect from bursts. The exact implementation is subject to change but is based on the following principles:

  • Updates more than 24h apart are almost always charged.
  • An average update rate is tracked per-feed. If a feed suddenly starts updating faster than the traditional rate the additional updates will not be charged.
  • The average is updated over time, so if a feed continues updating at the elevated rate credit consumption will slowly increase to match the new update rate.

FeedMail aims to be very low cost. To achieve this we need to keep our expenses predictable and fair. Otherwise we would need to overcharge some users to cover uncertainty and higher cost users.

To be fair to users who have purchased credits with the previous expectation in mind existing paid users will have their credit balance doubled to account for this difference. Based on our analysis this means that the remaining balance will last longer for all existing users. If any paid users feel like this will reduce the value of their credits please reach out to our support team and we will find the fair adjustment.

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