JazzJ,
Welcome to AAM.
The maximum waiting time would be 2 years, for any higher benefit on the new plan in the future, ie 2 years waiting to pay the lower excess.
Note; this is at the discretion of the provider. There have been situations where Laya have not applied this waiting time. VHI would be strict
in applying this waiting, I'm not sure about Aviva or Glohealth.
http://www.hia.ie/consumer-information/switchingupgrade-waiting-periods
Regarding upgrading outpatient day to day medical expenses, it depends on the company you're with as to what waiting applies.
Under 50 yrs - no waiting applies with any provider. New higher expenses can be claimed straight away.
Between 50 -65 yrs different waiting applies, with each company VHI, Aviva and Glohealth.
Over 65yrs a max of 2 years applies with VHI, Aviva and Glohealth.
Laya have no waiting times for outpatient expenses, regardless of age.
Regards, Snowyb