Theoretical ratio of the peak luminosities ℛ(T). A thin solid red line corresponds to alternative parameters: M_•, 6 = 0.1, M_dis = 10, the remaining lines correspond to M_•, 6 = 1,  M_dis = 1. Luminosities of L₁ − L₃ are power-law functions of ṁ, while the accretion rate is expected to drop by ṁ ∝ t^−p, where p ∈ {9/4, 1/2, 6/5} and the corresponding accretion rates are ṁ₁, ṁ₂, and ṁ₃, respectively. The solid green thick line shows the decline of the surface density of the disk due to viscous spreading, Σ, and the thick dashed line represents the combined effect of the Σ decline and canonical (−1.2) ṁ decline that crosses the value of 2 at 40 t_fb. The blue rectangle covers values 2–10. The minimum value of T is at 10 t_fb. The value of ℛ = 1.1 corresponds to our minimum expected detectable ratio and crosses the S_c line at 310 t_fb. The markers on the left side show the decline values for individual sources listed in the second column of Table 2. Finally, x, v, - belong to eRO-QPE1, eRO-QPE3, and GSN 069, respectively.