From FIXwiki

FIX Data Type TZTimeOnly

Name	BaseType	First introduced	Deprecated
TZTimeOnly	String	FIX.4.4

string field representing the time represented based on ISO 8601. This is the time with a UTC offset to allow identification of local time and timezone of that time.

Format is HH:MM[:SS][Z [ + - hh[:mm]]] where HH = 00-23 hours, MM = 00-59 minutes, SS = 00-59 seconds, hh = 01-12 offset hours, mm = 00-59 offset minutes.

Example: 07:39Z is 07:39 UTC

Example: 02:39-05 is five hours behind UTC, thus Eastern Time

Example: 15:39+08 is eight hours ahead of UTC, Hong Kong/Singapore time

Example: 13:09+05:30 is 5.5 hours ahead of UTC, India time

Notes

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