How to properly download expired commodity futures data

Being unable to get open interest data with the get_timeseries method, I tried to get all data with the get_data method.
I am unable to get identical close prices with the two methods, here's an example.
The way I get time series data which gives me the correct results excluding open interest:

ek.get_timeseries('BOH8^1','CLOSE',start_date='2018-02-28')
I get the data up to 14-03-2018.

If I use the get_data method:
ek.get_data('BOH8^1', ['TR.CLOSEPRICE.Date', 'TR.CLOSEPRICE'], {'SDate':'2018-02-28','EDate':'2018-03-18'})

I get data up to 12-03-2018. The Close price on that day according to the get_data output equals 31.43, but according to the get_timeseries output it is 31.56.
What is going wrong here? There are many differences between the two timeseries.

The open interest does get me data up to 14-03-2018 as expected.
ek.get_data('BOH8^1', ['TR.OPENINTEREST.Date', 'TR.OPENINTEREST'], {'SDate':'2018-02-28','EDate':'2018-03-18'})