I do not know the exact recommended timeframe but rinsing and repeating at the intervals you ask about would most definitely get Chase’s attention … NOT in a good way … IF Chase would even allow it. I believe 1 year is recommended for downgrading from a product with generous benefits, maybe the same timeframe for upgrading to a higher annual fee card. Some of it may be regulatory related to how often an issuer can change an AF. Some of the subject matter experts here will probably explain more accurately and thoroughly soon.