I would not classify those transitioning trichomes as full on amber, yet. Yes, some amber. Once you see capitulate trichomes with a wall to wall amber heads then you can start gauging amber trichs against clear, milky trichs for your desired harvest time.
Depending on the type of trichome, exceptional terpene production within the bulbous head can sometimes resemble amber tones/hues. Depends on the terpene too. Keep checking every day but know nothing radical will happen over night to where you check in the next day to find everything’s gone full amber from milky, etc.
Good luck