Schematic evolution of a ULX model arising from CHE of the more massive component in a compact binary with unequal masses and Z = 10^-3.5 ≃ Z_⊙/ 50 (see Sect. 3.1 for details). The phase of RLOF actually corresponds to three distinct mass-transfer phases. If at the moment of formation of the NS (or BH for the most massive secondaries) there is a kick in a favourable direction, a compact enough system can be formed such that a merger is possible in less than a Hubble time. For this system in particular, assuming a Maxwellian kick distribution with 1D root mean square σ = 265 km s^-1, there is a 67% chance that the binary is disrupted, and a 3.4% chance that it results in a NS+BH merger in less than a Hubble time. For simplicity, mass loss at the moment of formation of the first BH is ignored.