What happens when you change your pricing?

If we change our pricing, it will only affect future purchases. 

In other words, if you have a subscription your payment will not
change no matter what term you have signed up for and it will auto-renew
without an increase in price. However, if you want to sign-up for a new
subscription or switch to a different subscription term the cost will
be based on our new pricing model. If you cancel your account or if your
account gets canceled due to a failed re-occurring membership charge,
you will be subject to the new pricing if you choose to sign up

The same thing goes for pre-purchased credits.  The new pricing only applies to new credit purchases.

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