Printing system for double sided printing of tabbed sheets, comprising: - a transport mechanism comprising a first transport path extending along an image forming unit and a second transport path downstream of the image forming unit, which second transport path connects to the first transport path, such that a printed sheet (S1, S2, TS) is returned to the image forming unit; - a sheet flipping device for flipping sheets (S1, S2, TS) positioned along the second transport path, such that a sheet (S1, S2, TS) which has been printed on a first side on a first pass over the first transport path is oriented with its second side to the image forming unit on a second pass over the first transport path; - a transport switch for selectively directing sheets (S1, S2, TS) from the first transport path to the second transport path or from the first transport path to an output path, wherein the transport switch comprises: - a plurality of longitudinal transport fingers (32, 132), wherein each transport finger (32, 132) comprises: - a top support surface (33, 133) extending between an upstream end (38, 138) and a downstream end (39, 139) of the transport finger (32, 132), wherein the top support surfaces (33, 133) of the transport fingers (32, 132) are aligned to define a medium support plane; - a side face (34, 36, 134, 136) positioned below the medium support plane, wherein the side face (34, 36, 134, 136) is connected to the top support surface (33, 133) and extends between the upstream end (38, 138) and the downstream end (39, 139) of the transport finger (32, 132), characterized in that the side face (34, 36, 134, 136) of the transport finger (32, 132) comprises a longitudinal upward tab deflection face (35, 37, 135, 137) laterally inclined with respect to the medium support plane, such that a tab of a tabbed sheet coming into contact with the upward tab deflection face (35, 37, 135, 137) is guided onto the medium support plane of the transport finger (32, 132). - a transport mechanism comprising a first transport path extending along an image forming unit and a second transport path downstream of the image forming unit, which second transport path connects to the first transport path, such that a printed sheet (S1, S2, TS) is returned to the image forming unit; - a sheet flipping device for flipping sheets (S1, S2, TS) positioned along the second transport path, such that a sheet (S1, S2, TS) which has been printed on a first side on a first pass over the first transport path is oriented with its second side to the image forming unit on a second pass over the first transport path; - a transport switch for selectively directing sheets (S1, S2, TS) from the first transport path to the second transport path or from the first transport path to an output path, wherein the transport switch comprises: - a plurality of longitudinal transport fingers (32, 132), wherein each transport finger (32, 132) comprises: - a top support surface (33, 133) extending between an upstream end (38, 138) and a downstream end (39, 139) of the transport finger (32, 132), wherein the top support surfaces (33, 133) of the transport fingers (32, 132) are aligned to define a medium support plane; - a side face (34, 36, 134, 136) positioned below the medium support plane, wherein the side face (34, 36, 134, 136) is connected to the top support surface (33, 133) and extends between the upstream end (38, 138) and the downstream end (39, 139) of the transport finger (32, 132), - a top support surface (33, 133) extending between an upstream end (38, 138) and a downstream end (39, 139) of the transport finger (32, 132), wherein the top support surfaces (33, 133) of the transport fingers (32, 132) are aligned to define a medium support plane; - a side face (34, 36, 134, 136) positioned below the medium support plane, wherein the side face (34, 36, 134, 136) is connected to the top support surface (33, 133) and extends between the upstream end (38, 138) and the downstream end (39, 139) of the transport finger (32, 132),