How to get post-hoc tests using the Mixed Models < Generalised Mixed builder on SPSS

I am working in SPSS using the "Generalized Mixed" option under "Mixed Models" to run a GLMM. I have a repeated measures design. I am seeing whether repeated sessions (5) had an effect on dogs' approach (Y/N) to three bowl locations. My outcome variable is binary: approach yes/no. Session number (1,2,3,4,5) and Bowl Position (A,B,C) are fixed effects and DogID is a random effect. I have run a Generalised Linear Mixed Model with binary logistic regression link to the linear model but cannot see on the model builder SPSS display anywhere to run post-hoc tests. I would like to run Tukey's. I know that you can run post-hoc tests using the "General Linear Model" < "Univariate" tabs but this option cannot account for the binary outcome variable as far as I can tell. Does anyone know how to run post-hoc tests on this model builder in SPSS? I understand that many use R for this type of analysis but I am not proficient yet.