The truth told late still counts, but it arrives with baggage the early version never had to carry.

Late honesty is still honesty and it counts, though it arrives carrying what the delay added. Alongside the original fact there is now the gap, the time you knew and said nothing, which the other person has to account for as well. That extra weight is not a reason to keep waiting, since it only grows. It is a reason to notice that today is the lightest this will ever be.

If you are holding something, say it now and say the delay too. Name both plainly, without a defence. Then let them have whatever reaction the waiting earned.