Zoho Bookings <> Oulook

Zoho Bookings <> Oulook

When a user has their Outlook connected to Bookings should it be able to recognise existing meetings and not give those as available options ?
If so, how long is the sync time : ie If i were to put a private meeting at 3pm in my Outlook, how long would it take for Bookings to show that 3pm was no longer available ?

My users are finding that Bookings shows times available where it conflicts with Outlook.