The Mountain Road will close at 11am for delayed racing action around the TT course.
Organisers say the revised schedule will see the entire course shut at midday.
There'll then be a four-lap supersport race at 12.45pm, with a two-lap sidecar race due away from 2.50pm.
After that, solo machines will go out for a practice session at 4.05pm.
Roads should reopen no later than 5pm.
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