Hi,
Not sure where you are in Canada and whether it might be the same in your province - BC offers the following:
In some circumstances, while temporarily outside the province for work or vacation, individuals may retain eligibility for coverage during an ‘extended absence’ of up to 24 consecutive months, once in a 60 month (five year) period. To find out if you qualify, more information on extended absences is available on the MSP website.
I spoke with the folks at MSP and it was very easy to get the 2 year absence in every 5 years. It is not counted January to December so it works well - it is just the actual months in a 60 month period. I was told that if you are needing to go over that time they will consider it as long as you call before the 24 months has lapsed.