We study (In, Ga)(As, Sb)/GaAs quantum dots (QDs) embedded in a GaP (100) matrix, which are overgrown by a thin GaSb capping layer with variable thickness. QD samples are studied by temperature-dependent photoluminescence, and we observe that the QD emission shows anomalous temperature dependence, ie increase of energy with temperature increase from 10 K to∼ 70 K, followed by energy decrease for larger temperatures. With the help of fitting of luminescence spectra by Gaussian bands with energies extracted from eight band k.p.