FR-IAS16-PPE Revaluation upwards and downwards

Hi Chris

I have a question in chapter 5 PPE, example 2, if you could help me out understand it please.
https://www.youtube.com/watch?v=0bOdCnwSKu0

I have not clear why we debited the OCI with the amount of 3.850
I understand that when we have revaluation gain the amount goes to OCI, so in 31/12/14 (first revaluation upwards) the gain is 4.400 (OCI)

At the same time, Revaluation reserve should be credited ->4.400 minus 550 = 3.850

I dont understand how OCI went from 4.400 to 3.850. Do we deduct and from OCI the amount of the depreciation loss (-550) as we do in revaluation reserve account?

Thank you
Evaggelia