Evolution of the donor star’s stellar radius R_don, Roche lobe radius R_RL, and the associated mass transfer rate Ṁ over time for the intermittently accreting system 110650060, an archetypical BABDef system. The dashed green line indicates the mass transfer rate during the Case BA mass transfer episode of the system and the dashed red line denotes the mass transfer rate during the (comparatively short) Case BB mass transfer episode. Labels indicate the point at which the donor leaves the He MS (i.e., the end of its core helium burning phase) and the extent of the gap between the two mass transfer episodes (accretion gap).