We consider the time evolution of two entropy-like quantities, the holographic entanglement entropy and causal holographic information, in a model of holographic thermalization dual to the gravitational collapse of a thin planar shell. Unlike earlier calculations valid in different limits, we perform a full treatment of the dynamics of the system, varying both the shell's equation of state and initial position. In all cases considered, we find that between an early period related to the acceleration of the shell and a late epoch of saturation towards the thermal limit, the entanglement entropy exhibits universal linear growth in time in accordance with the prediction of Liu and Suh. As intermediate steps of our analysis, we explicitly construct a coordinate system continuous at the location of an infinitely thin shell and derive matching conditions for geodesics and extremal surfaces traversing this region.Introduction. The equilibration dynamics of strongly coupled systems is an active topic of research, motivated equally by studies of the thermalization process of heavy ion collisions and quantum quenches in condensed matter systems (see e.g. [1] for a review). Approaching the problem in the cleanest setup possible -N = 4 Super YangMills (SYM) theory in the limit of large N c and 't Hooft coupling λ -it may be formulated as follows: Given various physically motivated initial conditions, how does the gravitational system evolve towards its final state involving a black hole in AdS 5 space-time? And what are the implications of this gravitational dynamics on the dual field theory side; in particular, how do different physical quantities behave during the equilibration process?In the context of heavy ion physics, recent years have witnessed remarkable progress in the holographic description of the collision. This includes extensive work on colliding shock waves in strongly coupled N = 4 SYM theory [2-6], equilibration in inhomogeneous and anisotropic systems [7][8][9][10][11], and even studies relaxing the assumptions of infinite 't Hooft coupling [12][13][14][15] and conformal invariance [16]. Typical quantities considered in these setups are expectation values of different components of the energy momentum tensor as well as two-point functions related to transport or photon production [17,18]. So far, more complicated observables have been considered only in the simplest setups, such as the quasistatic or Vaidya limits of a gravitationally collapsing planar shell moving either arbitrarily slowly or at the speed of light,