The TT's senior medical officer is expressing serious concerns over the decision to add an extra hour to race practice sessions this year.
TT organisers say an extension is vital to allow competitors in the inaugural green emissions XGP event some practice time.
Dedicated extra practice sessions have been added from Tuesday to Friday of practice week, meaning roads around the mountain will close at 4pm and the rest of the course at 5pm, an hour earlier than usual.
Medical Services Director for Isle of Man Motorsport Dr David Stevens is concerned that medics and marshals won't be able to get to their posts in time.
He told Manx Radio:
"Several of my medics, that's not only doctots but paramedics and the people who man the ambulance, have phoned to say there's no way they can get off early.
"Most of them finish at 5pm or 5.30pm and they already struggle to get out on the course for 6pm, but to bring it forward an hour...
"They are effectively saying that they can't actually make it, and from previous experience some of their employers are not exactly very, very friendly towards the races and it's very unlikely that they'll just allow them to go off that bit earlier."
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