I would solve it like this:
1.) Use Convert Tag -> Tag with
This will replace the right two numbers from the %DATE% to the written month name and then adds the left two numbers from the %DATE% at the end ot the month name, separated with a space.
Please complete all 12 possible month numbers and names in the format string.
This only works if your days and the month are always saved in the format DDMM in %DATE%.
As always: Please backup your tracks before you test and check this conversion.