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Yes I have seen stabling used there often, but I have also seen it used for passenger terminators when engineering works stop trains going beyond Tonbridge. Not a regular use of course, but it does happen.
First one up in the morning (via mid-Kent) used to go in service off 4 but now the platform 4 set goes empties to Orpington to form a Vic stopper. The first passenger London train now comes off Jubilee sidings and goes from platform 2.
As others have said, it sees use during engineering works, for example this Sunday (21/7) there's an hourly service operating in and out and a half-hourly service on Sunday 28th.