however oriented on practical and efficient computations of multi-particle off-shell amplitudes using helicity method and computer codes. As stated before, in CCH the UGDs undergo BFKL evolution. In our extensions of CCH approach we allow the UGDs to undergo more complicated evolution equations, which are more suitable for jets. More details will be given in Section \[sec:evolution\_eqs\]. Yet another modification of the CCH formula comes from the fact that the present study concerns the system of dijets where one of the jet is forward, while the second is in the central region. From $2\rightarrow2$ kinematics it follows then, that $x_{A}\ll x_{B}$ (or the opposite), except for the small corner of the phase space. Since $x_{B}$ is typically of the order of $0.5$ the usage of small $x$ evolution for $\mathcal{F}_{g^{*}/B}$ is questionable (this is similar to dilute-dense system considered e.g. in [@Dominguez:2011wm]). Therefore we use collinear approach on the $B$ hadron side [@Deak:2009xt]. Technically, one takes the collinear limit in $d\hat{\sigma}_{g^{*}g^{*}\rightarrow2j}$ by sending $k_{TB}\rightarrow0$ to obtain a sub-process with one off-shell gluon $d\hat{\sigma}_{g^{*}g\rightarrow2j}$ (the off-shell amplitudes have well defined on-shell limit). In this limit one has to take into account also sub-processes with initial state on-shell quarks, $d\hat{\sigma}_{g^{*}q\rightarrow2j}$. The remaining 