assembeling BC matrix after using "pdebound" (user defind matrix)

Hi, i worte a user defined function for the construction of the boundary conditions. the output of this function is 4 different matrices instead of one boundary condition matrix which is needed in order to use the "assempde" function for solving the pde problem. is it possible to create one boundary condition matrix from those 4 matrices (H, R, Q, G) ?

thank you for your help