Dun Filly?

[Stable_Of_Champions]

So I have had foals like this before where I can't really tell the colour of. I don't know if I should wait until she is older to determine her colour since I have had foals that look like her and end up being dun or something along those chestnut-base-coat colour lines, she just looks kind of lighter then what a dun foal looks like. Any help would be great!
Profile: https://www.horseworldonline.net/horse/profile/3443264

[BlackOak2]

So I have had foals like this before where I can't really tell the colour of. I don't know if I should wait until she is older to determine her colour since I have had foals that look like her and end up being dun or something along those chestnut-base-coat colour lines, she just looks kind of lighter then what a dun foal looks like. Any help would be great!
Profile: https://www.horseworldonline.net/horse/profile/3443264

Okay... because of your wording, I have to say this first:
Any base coat color can be affected by dun. So Black and Chestnut base coats can have dun. This includes agouti coats (bay, wild bay, brown). Agouti isn't a base coat as it's considered 'black-based' but for ease of understanding, it's often lumped into the 'base coats' as in: black, agouti, chestnut bases.

Anyway.
She's a bit young to tell for sure, but I do see a suspicious strip along the mane and it continues along the backbone. Do you see it? That reddish, pale-ish line? It turns to a dingy yellow along her back. This usually is indicative of dun.

So I'd say, yes.

You might find some help in dun identification if you swung by the study:
viewtopic.php?f=13&t=11515
It can help with teaching the eye to 'see' the signs.

[Stable_Of_Champions]

Thank you so much! I see it now that I look at her, it will take time but I'll make sure to watch for any signs and check out the topic