Crossword puzzle clue "like ones starting over"

Like ones starting over

50 different ones were released over a 10-year period starting in 1999

Watch over and over and over and over again?

Start over, starting over

Starting a project ... and what the letters between the starting and ending pairs of letters in each starred answer are doing?

Ones starting up start-ups, say

Ones who are always starting something?

Ones starting actions