National Archives BT377/7 Registry of Shipping and Seamen, Royal Navy Reserve Ratings' Records.
When will they be added?
Fife Military Project commented
They are one of a few groups of records that are being being added manually by the volunteers, personally I have already added over 1000 RNR men although obviously that is only a small percentage of the total required and it will take a good while longer before all the RNR men are added. If you have any specific men you would like added sooner please post their names and numbers here and I will bump them up the list and get their lifestories created for you.