Premium Registry Domains - Can they increase renewal price?

I found this online:

Registry operators and registrars are free to charge a premium for certain names at their discretion, assuming they are otherwise in compliance with the terms and conditions of their agreements.

That said, a registry operator or registrar may not implement/impose abusive or discriminatory renewal pricing practices without the written consent of the applicable registrant at the time of initial registration. This includes, for example, the requirement for advance notification of any price increase and the right to renew the registration at the price prior to such increase for a period of up to 10 years (i.e., the price may be locked in).

For more information about your rights and responsibilities as a domain name holder (registrant), please see our registrant rights and responsibilities page: icann (dot) org/resources/pages/benefits-2013-09-16-en.

Based on the Expired Registration Recovery Policy (ERRP) Policy found at: icann (dot) org/resources/pages/errp-2013-02-28-en, Registrars must make their renewal fees, post-expiration renewal fees (if different), and redemption/restore fees reasonably available to registered name holders and prospective registered name holders at the time of registration of a gTLD name. At a minimum, these fees must be clearly displayed on the registrar's website and a link to these fees must be included in the registrar's registration agreements.