At some point in the decreolization process, however, xenolectal structures become masked by surface-structure mimicry of the matrilect, so that the apparent degree of xenolecticity of the evolving mimolect drops below the real level, as represented by the crossover of A-B and C-D.
Source: wiktionary
In the process, as substantial numbers of black speakers underwent decreolization, their decreolized speech, although technically a mimolect, would have much of the surface form and therefore social status of a true matrilect, and would itself then serve as an additional model for those speakers further behind in the decreolization process.
Source: wiktionary
As a xenolect develops, it becomes mimolect, that is, a variety whose external appearance resembles that of another (Stewart, 1989: 263-280).
Source: wiktionary