Tasting room / retail separation from DSP

[Joshnamu]

Hello everyone! My partner and I are starting a new distillery in the Boston area which we're very excited about. We have a prospective location picked out and are in negotiation for a long-term lease, but we're not sure the layout of the facility is appropriate. The facility is one large warehouse-like building with high ceilings, so we already know we will have to construct a floor to ceiling wall to split the warehouse into the DSP and retail / tasting areas, each with their own separate egresses to the outside. However, the building only has one bathroom which is currently located in the planned area for the DSP.

Would it be possible to designate the bathroom as "general premises" in the DSP and have customers walk through the general premises of the DSP in order to access the bathroom? The TTB call center suggested we would need to build a permanent 4ft. physical wall / barrier to separate the bonded premises from the general premises in the DSP to comply with security requirements, but are there additional requirements regarding unsupervised access to the general premises portion of the DSP?