The phrase "more halfyearly" could be replaced with synonyms such as "semi-annually", "twice a year", or "bi-annually". Other options may include "every six months", "half-yearly", or "two times per annum". Depending on the context, different synonyms may be more suitable. For example, in a financial or business context, "semi-annually" would be appropriate. In other contexts, "two times per annum" or "bi-annually" might be preferred. Regardless of the specific synonym used, all convey the meaning of occurring twice within a twelve-month period.