Having dyed my hair in cool reds for perhaps a decade .... Do not 'refresh' the lengths with permanent or demi permanent dye, over time this causes damage making the ends more porous worsening the chances of a mismatch between the older and younger hair. Use a peroxide free semi permanent on the lengths.
2a-2c, medium texture, porous/ colour treated. Three years CG. Past bra strap length heading for waist.

CO-wash: Inecto coconut/ Elvive Volume Collagen
Treatments: Komaza Care Matani, coconut/ sweet almond/ fractionated coconut oils, Hairveda Sitrinillah
Leave in: Fructis Sleek & Shine (old), Gliss Ultimate Volume, various Elvive
Styler: Umberto Giannini jelly, Au Naturale styling gelee
Flour sack towel, pixie diffuse or air dry.
Experimenting with: benign neglect