Splitting single .t6 files into multi-year .t6 files

At the moment I am developing a strategy for the Russell3000.

The history for each stock is stored under a single .t6 file, which makes data management quite complex.

Is there a way to split each historical .t6 file containing daily data into separate yearly files as it happens with M1-files.

Also everytime I want to download updated data for the last few days, the whole dataset of the stock is downloaded again.

Is there a way to just append the file as is the case with M1-data.

Thanks.

Splitting .t6 files can be done with the dataset commands, find the first bar of this and next year with dataFind, then use dataSave with the two row numbers for saving the year.

Thanks Spirit.
Wouldn't have found that on my own.

Cheers