Rent increase for a sitting tenant: RERA guidelines or free market rate?

Dear Sir/Madam,

I recently purchased a property with a sitting tenant who has a tenancy contract expiring on 20/08/2023. The current rent is 35,000 AED per annum.

If I wish to increase the rent, can I give the tenant a 90-day notice and increase the rent to (a) the free market rate, (b) the RERA index range, or (c) just the RERA prescribed percentage (5%, 10%, 15%, or 20%), based on the difference between the current rent and RERA index?