Starter question day 13

I am on day 13 with my starter, as of yesterday it has finally started doubling 2 days in a row, I have been feeding a 1:2:2 every 24ish hours. This picture is taken 19 hours since the last feed (about 6pm last night.) I hear it needs to be doubling within 6 hours before you can use it, I see so much conflicting information everywhere. Can anyone share any wisdom with me or give me some advice if I need to change anything and when it should be ready to use?

I am on day 13 with my starter, as of yesterday it has finally started doubling 2 days in a row, I have been feeding a 1:2:2 every 24ish hours. This picture is taken 19 hours since the last feed (about 6pm last night.) I hear it needs to be doubling within 6 hours before you can use it, I see so much conflicting information everywhere. Can anyone share any wisdom with me or give me some advice if I need to change anything and when it should be ready to use?