Hi Bert,
According to the original design, the 'big' davits (gantry davits) should be present on both sides.You can see the original configuration at the following link:
hospitalshipbritannic.com/rms_britannic.htm
When Britannic was requisitioned as a hospital ship,only 5 sets of davits had already been installed and there was simply no time to install the rest.As a temporary solution, the shipbuilders chose to install the smaller Wellin davits (those also present on Titanic) in order to reach the planned lifeboat capacity.That's why you see a single set of gantry davits near the first funnel.
Regards,
Michail