Time calls may need to be UTC or local time.
For example when inbound or departing calls to a CTAF we use local time. When talking with ATC its often UTC
However we need to note that when transmitting time we often use just two numbers, and that could be confused with a runway number or other numbers. To save confusion we prefix it with “time”.
So to refer to UTC 0120 we would pronounce Time Too Ze Ro
For local time 9:39 we would say Time Tree Nin Er
If a four digit time was necessary to stop confusion we would simply say Time and the four digits with correct pronunciation.
And if it was possible to confuse local time with UTC time we would prefix it bay saying Local Time Tree Niner or UTC time Too Ze Ro. However the occasions you need to prefix it with UTC or Local are very limited.