Tax benefit on continued elss beyond 3 years

Hello,

I made investment in an ELSS tax saving MF in 2016. It will qualify for completion of the necessary 3-year tax period this year (2019).

My question is - Instead of enashing the MF units, if I continue to hold on to it for another 3 years, can I claim tax benefit again for the year 2019 for the holding period 2019-2022? In that case, what will be the investment value to consider as MF value keeps changing each day?

OR am I necessarily required to encash the existing MF units, and then re-purchase it again to claim tax benefit?

Please let me know.

Thanks